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Old 04-03-2005, 10:14 PM   #1
sandy eggo
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Default Anybody towing a TM with BMW X5 4.4i ?

Hi All -

We're seriously thinking about buying a TM 3023 or 3124KB but are finding it difficult to verify what our BMW X5 4.4i will tow (and tongue weight, etc).

A few details on the BMW:
2001 model year
4.4 liter V-8
282 HP, a bit more than that in "grunt" (ft. lb.) if memory serves
Factory tow-hitch
Automatic with sport/manu-matic mode (can keep transmission in a gear within safe RPM limits)

The owner's manual says nothing about towing limits or tongue weight. All I can find on the Internet is that it is supposedly rated to 6,000 lbs.

When I check the TM website, it confirms the 6,000 lb weight limit - which implies I'd be ok towing virtually any TM product. However, I'm a bit nervous that given the combination of wheelbase, gear ratios, etc, etc, that I may be in for a nasty surprise with the combintion of my X5 and a 3023 or 3124KB.

Anybody using a X5 4.4i out there in TM land - if so, what model are you towing and how's it going?

Even if you're not using a X5 as a towing rig but can "speak" with some authority on whether or not I could tow the 3023 or 3124KB, please let me know.

Oh yeah, we live in Southern CA and would plan on taking the TM pretty much anywhere in the in the West (sea level to Rocky Mountains).

Thanks!
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Old 04-04-2005, 07:07 AM   #2
RockyMtnRay
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Join Date: Jul 2001
Location: Colorado Springs, CO
Posts: 816
Default May be do-able

Quote:
Originally Posted by sandy eggo
Hi All -

We're seriously thinking about buying a TM 3023 or 3124KB but are finding it difficult to verify what our BMW X5 4.4i will tow (and tongue weight, etc).

A few details on the BMW:
2001 model year
4.4 liter V-8
282 HP, a bit more than that in "grunt" (ft. lb.) if memory serves
Factory tow-hitch
Automatic with sport/manu-matic mode (can keep transmission in a gear within safe RPM limits)

The owner's manual says nothing about towing limits or tongue weight. All I can find on the Internet is that it is supposedly rated to 6,000 lbs.

When I check the TM website, it confirms the 6,000 lb weight limit - which implies I'd be ok towing virtually any TM product. However, I'm a bit nervous that given the combination of wheelbase, gear ratios, etc, etc, that I may be in for a nasty surprise with the combintion of my X5 and a 3023 or 3124KB.

Anybody using a X5 4.4i out there in TM land - if so, what model are you towing and how's it going?

Even if you're not using a X5 as a towing rig but can "speak" with some authority on whether or not I could tow the 3023 or 3124KB, please let me know.

Oh yeah, we live in Southern CA and would plan on taking the TM pretty much anywhere in the in the West (sea level to Rocky Mountains).

Thanks!
I can't recall any prior posts here from anyone who's using an X5 for towing (you might check the Tow Vehicles forum at RV.NET). But who knows...we may have another X5 owner who's just been lurking...and if so, please speak up!

However, until such a person appears, I'll take a stab at answering your questions.

First of all, BMW markets the X5 as a Sports Activity Vehicle and not as a plebian Sports Utility Vehicle. That does make we wonder about issues like frame/body strength, hitch receiver attachment considerations/issues (allowable tongue weights become critical here) that are generally not a problem with true SUVs (which the manufacturers assume will be used for moderately heavy duty towing) but that could be a problem with a vehicle that's marketed for sports activities. So, here you are on your own...talk to dealers, factory reps, search the BMW online forums, etc.

But moving on to the basic specs...the engine is rated at 324 ft-lbs of torque at a decently low 3600 RPM (when it comes to towing, the Horsepower rating is almost meaningless since that's measured at about the Redline RPM and no-one in their right mind will continuously run the engine near the Redline). The X5 apparently has a 3.64:1 axle ratio. This combination of torque, axle ratio and a 5 speed transmission should be more than sufficient for all western states towing...even in the high altitudes of the Sierra and the Rockies. I did say "should" because, as with the frame, the strength of the transmission for towing is an unknown. If the X5 does not have an external transmission cooler, you should certainly consider adding one before doing any towing.

The other critical spec...wheelbase...at 2,819 mm (about 111 inches), this seems sufficient for either a 3023 or 3124 TM. Not much more than sufficient, but other people are successfully towing this size of TM with SUVs that have 110 to 112 inch wheelbases. Wheelbase is critical, BTW, because it is the primary determinant in whether the Tow Vehicle can exert sufficient leverage on the trailer to handle sharp mountain curves (especially those that are also steeply descending) and the traditional bugaboo of trailer sway from semi-truck bow waves and cross winds.

So...on paper...your X5 looks like it should be able to tow any TM up through a 3124 with a reasonable level of spare capacity (a fully loaded 3124 or 3023 will weigh around 5000 lbs so even with a 6000 lb tow rating there isn't a lot of spare capacity, especially at high altitude).

But, given the demographic and usage styles that the X5 was developed and marketed for (and BMW's reputation as the builder of sports sedans and sports cars)...I personally would do a lot of investigating into just how much strength there is in the frame, hitch attachment provisions, and maybe also the transmission before I took the plunge of buying a trailer.
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Ray

I use my TM as a base camp for hiking, kayaking, mountain biking, and climbing Colorado's 14ers


The Trailer: 2002 TM Model 2720SL ( Mods: Solar Panels (170 Watts), Dual T-105 Batteries, Electric Tongue Jack, Side AC, Programmable Thermostat, Doran TP Monitor System)

The Tow Vehicle: 2003 Toyota Tundra V8 SR5 4X4 w/Tow Package (Towing & Performance Mods: JBA Headers, Gibson Muffler, 4.30 gears, Michelin LTX M/S Tires, Prodigy Brake Controller, Transmission Temperature Gauge)


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Old 04-04-2005, 09:58 AM   #3
sandy eggo
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Default I'll do my homework - thanks!

Ray -

I really appreciate the work you put into the reply - exactly what I was looking for. Well, actually, I was looking for a definitive "yes or no" but in reality your answer probably serves me better.

I'd like to think that although it is marketed as a "Sports Activity Vehicle", if the engineers and manufacturer gave it a factory trailer hitch option and a 6,000 towing capacity that they actually mean it (and beefed up the frame and transmission to support that application). That said, I'm scratching my head to recall if the X5 was built new from the ground up or if it simply uses the 5 series frame...I know it won't take me long to get to the bottom of that one.

True, BMW is known for their sports sedans but they're also known for extremely high engineering standards and quality workmanship. I would be dismayed/surprised to find out that in reality the X5 should not tow more than a couple jet-skis.

BTW, my X5 is alpine white and the thought of it pulling a shiny white TM behind it...well, that would be a pretty cool picture. Imagine the looks as I chug like a freight train past the other cars going up the mountain gasping for air (gotta love BMW's VANOS**!). Ok, maybe I'm spending too much time with my 3 year old's train set.

Rick

** VANOS, in case you're wondering, is BMW speak for their steplessly variable valve timing. Breathe baby, breathe!
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Old 04-04-2005, 10:54 AM   #4
RockyMtnRay
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Join Date: Jul 2001
Location: Colorado Springs, CO
Posts: 816
Default Re Bavarian Elves and Chugging

Quote:
Originally Posted by sandy eggo
Ray -

I really appreciate the work you put into the reply - exactly what I was looking for. Well, actually, I was looking for a definitive "yes or no" but in reality your answer probably serves me better.
Welcome...did the best I could. Not many people are using European vehicles to tow trailers.
Quote:
I'd like to think that although it is marketed as a "Sports Activity Vehicle", if the engineers and manufacturer gave it a factory trailer hitch option and a 6,000 towing capacity that they actually mean it (and beefed up the frame and transmission to support that application). That said, I'm scratching my head to recall if the X5 was built new from the ground up or if it simply uses the 5 series frame...I know it won't take me long to get to the bottom of that one.

True, BMW is known for their sports sedans but they're also known for extremely high engineering standards and quality workmanship. I would be dismayed/surprised to find out that in reality the X5 should not tow more than a couple jet-skis.
Welll, you never know with those Bavarian (or Black Forest) "Elves"...they definitely make some jewel like engines but, being Europeans where fuel is extremely expensive, there's also a big emphasis on using lots of fancy technology but not lots of engine displacement or any more steel (heavy stuff) than needed for the intended purpose (which was very unlikely to be serious towing). The Japanese "Ninjas" that designed/built my Toyota Tundra have many of the same traits...and my truck certainly doesn't have same spare frame/suspension/axle strength that a typical domestic half ton truck has. So do be sure to investigate this very thoroughly as regular towing of a semi-heavy, semi-long trailer puts stresses on a vehicle that are just not encountered in normal "activity" usage.

BTW, when I lived in Germany back in the '80s I made a trip to the Bayerische Motoren Werke in Munich...the company has a really cool museum there.
Quote:
BTW, my X5 is alpine white and the thought of it pulling a shiny white TM behind it...well, that would be a pretty cool picture. Imagine the looks as I chug like a freight train past the other cars going up the mountain gasping for air (gotta love BMW's VANOS**!). Ok, maybe I'm spending too much time with my 3 year old's train set.

Rick

** VANOS, in case you're wondering, is BMW speak for their steplessly variable valve timing. Breathe baby, breathe!
Yes....my Tundra is "Natural" (i.e. Arctic) white and that is a good combo with the newer very white TMs.

Your mention of the chugging and train set gave me visions of you repeating the mantra of The Little Engine That Could: "I think I can, I think I can...."

Variable valve timing is not, believe it not, all that big a deal for towing. Toyota added variable valve timing to the 4.7L Tundra engine for '05 and I'm not all that impressed....certainly not impressed enough to want to trade my '03 in for a new one. The goal in towing is to have maximized torque in the low to mid RPMs...this is what will get a rig moving from a standstill and what will keep you going up grades without having to downshift to get the high RPMs. And you certainly don't need variable valve timing to optimize low end torque...but you do need real long intake runners, very little valve overlap, and an exhaust system (including headers) that's tuned for minimum backpressure at low RPM. Among other things that means a single outlet exhaust (although great for high RPM, duals are generally bad for low end torque).

Variable valve timing allows smallish engines to have decent (but not great) low to mid range torque, yet avoid the normal drop off of torque as the engine speed rises above about 3500 to 4000 RPM. Since Horsepower is basically RPM times torque, that results in some pretty impressive HP numbers out of smallish (under 5.0L) engines...which is exactly what BMW (and Toyota) have achieved. However, in my not-so-humble opinion ( ), if you don't have enough low/mid range torque to pull most grades with the transmission in the gear that provides a 1:1 in/out ratio (usually 4th on 5 speed automatic with OD)...and you have to depend on regularly using high revs, then your vehicle needs some serious towing-oriented modifications or you don't have the right vehicle. That was exactly the situation I was in about a year ago...and after doing those mods (headers, muffler that's tuned for low/mid RPM, and change to 4.30 axle gearing), I now have a vehicle that can pull most steep and high altitude (up to 12,000 feet elevation) grades without any downshifts...with trailer in tow.
__________________
Ray

I use my TM as a base camp for hiking, kayaking, mountain biking, and climbing Colorado's 14ers


The Trailer: 2002 TM Model 2720SL ( Mods: Solar Panels (170 Watts), Dual T-105 Batteries, Electric Tongue Jack, Side AC, Programmable Thermostat, Doran TP Monitor System)

The Tow Vehicle: 2003 Toyota Tundra V8 SR5 4X4 w/Tow Package (Towing & Performance Mods: JBA Headers, Gibson Muffler, 4.30 gears, Michelin LTX M/S Tires, Prodigy Brake Controller, Transmission Temperature Gauge)


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Old 04-04-2005, 12:04 PM   #5
sandy eggo
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Thanks again Ray - a real education.

I was able to find a couple data points that indicate that the X5 was built new from the ground up and not simply reusing the 5 series frame, etc. That said, it was optimized to have car-like handling and not haul a ton of gravel.

Agreed that there is no "replacement for displacement" and in this game it is torque that matters. The Elves that conjured up the X5 seem to have agreed as well - and graced the X5 with the same 4.4 liter V-8 that powers the last generation 7 series with plenty of low end torque (thanks for that info). Not exactly a miserly, pip-squeak of an engine normally associated with the Europeans! Also, the X5 is built like a tank and weighs in at something like 5,000 lbs - so not sure what constitutes "a lot", but it seems like the Elves didn't scrimp on steel either. Point well taken though and I will definitely check in with my friends on the BMW forums to see what their advice is.

I understand your point about torque being the main factor in chugging up the mountain but doesn't the engines ability to breathe at the higher altitudes have any impact on how efficiently that power & torque is produced? My (non-engineering) brain says it certainly should have an impact. The effect of VANOS like technologies is that it allows the engine to breathe as it normally would at sea level even at mountain altitudes. Sort of like "altitude training" for cars?

Anyway, maybe I should just get a TM and come out to CO for a good old fashioned tractor pull.
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Old 04-04-2005, 02:21 PM   #6
RockyMtnRay
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Join Date: Jul 2001
Location: Colorado Springs, CO
Posts: 816
Default Re Engine 'breathing'

Quote:
Originally Posted by sandy eggo
I understand your point about torque being the main factor in chugging up the mountain but doesn't the engines ability to breathe at the higher altitudes have any impact on how efficiently that power & torque is produced? My (non-engineering) brain says it certainly should have an impact. The effect of VANOS like technologies is that it allows the engine to breathe as it normally would at sea level even at mountain altitudes. Sort of like "altitude training" for cars?
Methinks you misunderstand what the variable valve timing is doing. First, it is not going to allow your engine to compensate much, if any, for the lowered atmospheric pressure of higher altitude. Only some form of waste-gated forced induction (i.e. supercharging or turbocharging) can provide substantial compensation for altitude. Absent forced induction (with a boost pressure compensating wastegate), a given engine design will "breathe" equally well (or equally poorly) regardless of altitude. An engine that breathes well at 12,000 feet will also "breathe" very well at sea level and vice versa.

What variable valve timing can do...particularly if combined with variable intake runner lengths...is change the shape of the torque curve with respect to RPM.

As mentioned previously, to optimize the torque of an engine for low to mid RPM, it should have long intake runners, very little valve overlap (and the exhaust doesn't open until very near the end of the power stroke), and long but fairly small diameter exhaust header primaries. Unfortunately, this combination has the side effect of causing a sharp drop off in engine torque at higher RPM...the torque curve is fairly flat up to about 3500 RPM but drops precipitously thereafter. This is the classic torque curve of a truck engine...lots of low grunt but no top end.

By contrast, to optimize an engine for high RPM, it should have short intake runners, quite a bit of valve overlap (and the exhaust valve should open well before the end of the power stroke), and the exhaust should be tuned for scavenging at high volumes and high rates of exhaust flow (e.g. headers have short fat primaries and there will be dual mufflers (and probably dual pipes)). The downside to this kind of tuning is the torque curve rises from very low values to peak (and more or less stays flat thereafter) only after the engine gets over about 3500 RPM. This is the torque curve of a race car or a classic sports car...lots of go only if you keep it really revved up.

What variable valve timing does is, depending on RPM, partially retune the engine between these two extremes...as the RPMs increase, the valves are retimed from little valve overlap/late opening to more overlap and earlier valve opening. On some engines with really complex cams, the entire cam profile is switched toward longer opening duration at high RPM. Some engines (like the new '05 Tundra engine) even go one step further and have dual intake runners for each cylinder...at low RPMs the engine control unit uses manifold valving so that a longer intake runner in the manifold is feeding air to each intake valve, and then as RPMs increase, the ECU switches to using the short intake runners inside the manifold. I don't know if the BMW Elves used this particular self-tuning trick but wouldn't be surprised if they did.

The net of these self-tuning operations is a variable valve timing engine (particularly one with varying length intake runners) maintains a fairly flat torque curve from very low to very high RPM...which means pretty decent low end grunt (torque)and also very impressive high end horsepower. If you want to phrase all this in terms of an engine's ability to "breathe" (a term I'm not very fond of), you could say that variable valve timing allows the engine to breathe equally well at all RPMs...not just breathe well in a portion of its RPM range.

It's not inconceiveable (though also not likely) that the BMW Elves are using a pressure sensor to slightly tweak the response of the VANOS for differences in atmospheric pressure. However, since intake air/exhaust gas velocity doesn't change much with altitude, or more precisely, doesn't change nearly as dramatically with altitude as it does with change in engine RPM, the overwhelming majority of the VVT effect will be proportional to engine RPM and not to altitude. So I'm not going to flat out say that your engine's VANOS doesn't compensate for altitude but I would be highly surprised if it's more than a 1 or 2 percent compensation. Certainly not a really noticeable compensation.

Quote:
Anyway, maybe I should just get a TM and come out to CO for a good old fashioned tractor pull.
Heehee...with my mods I'm getting around 360 ft-lbs of torque (at a relatively low 3200 RPM)...and a whole lot of torque multiplication from the 4.30 axle gearing. To quote El Presidente Bush: "bring it on"
__________________
Ray

I use my TM as a base camp for hiking, kayaking, mountain biking, and climbing Colorado's 14ers


The Trailer: 2002 TM Model 2720SL ( Mods: Solar Panels (170 Watts), Dual T-105 Batteries, Electric Tongue Jack, Side AC, Programmable Thermostat, Doran TP Monitor System)

The Tow Vehicle: 2003 Toyota Tundra V8 SR5 4X4 w/Tow Package (Towing & Performance Mods: JBA Headers, Gibson Muffler, 4.30 gears, Michelin LTX M/S Tires, Prodigy Brake Controller, Transmission Temperature Gauge)


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Old 04-04-2005, 03:15 PM   #7
Cobra500
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I have to disagree a bit- monster torque is great for towing if you do not want to shift to a lower gear and economy is not an issue. Transmissions are built to trade convert hp (high rpm) for torque- they are really torque multipliers. Variable timing provides an aid for an engine to produce good torque numbers in both high AND low rpm ranges, not either/or like conventional camshaft timing. In reality, it is better for the engine to shift down to a higherr gear (to pull a long grade) than to lug the engine.

The only red flag Id have regarding some of the Jap/Euoropean peak-HP wonders involves turbocharging. Towing is murder on a turbocharged GASOLINE motor (diesel motors tow very well with turbocharging...). The problem involves heat generation and detonation, a devestating byproduct of high heat.
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Old 04-04-2005, 03:27 PM   #8
sandy eggo
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Default Tongue Weights of TMs?

Yeah, I'm sure I'd get thrashed...but it would be fun trying.

I've had practically zero luck finding much of anything useful out on the vast Internet regarding real-world towing capabilities of the X5 4.4i. I did find this knowledge nugget on rv.net (thanks for the pointer).

One big CAUTION if you want to tow with a BMW SUV. Unless they have changed their specs, you can tow 6000#'s with their BIG SUV, but the hitch weight can no exceed 600#'s. Thus if you have a trailer that needs a 15% tongue weight, you are really limited to a 4000# maximum trailer weight! I verified this with BMW. They say if you exceed that there is no warranty on related failures.

So, let's assume my hitch is rated for 600 lbs on the tongue. My new/next question is if the tongue weight (as specified on the TM website) of the 3124KB is 448, I should be fine; however, is that the tongue weight of a "dry" TM. What would the tongue weight need to be of a fully loaded 3124KB? And what are the safe tolerances for tongue weights - i.e., if the tongue weight is 600 lbs and the hitch is rated at 600 lbs, I'm assuming that this is not a safe scenario.

Thanks again for the help.

Rick
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Old 04-04-2005, 03:43 PM   #9
RockyMtnRay
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Default More torque means less need for downshifting on routine grades

Quote:
Originally Posted by Cobra500
I have to disagree a bit- monster torque is great for towing if you do not want to shift to a lower gear and economy is not an issue. Transmissions are built to trade convert hp (high rpm) for torque- they are really torque multipliers. Variable timing provides an aid for an engine to produce good torque numbers in both high AND low rpm ranges, not either/or like conventional camshaft timing. In reality, it is better for the engine to shift down to a higherr gear (to pull a long grade) than to lug the engine.
Actually we are in agreement on the general prinicipal...it's a matter of specifics about the exact RPM and exact gear ratio, and the length/steepness of the grades.

As someone who does mostly mountain towing (I don't think I've ever towed more than 10 consecutive miles on truly flat terrain), my views are this:
  • To avoid downshifts (or torque converter clutch unlock) on even slight grades, you should tow in the gear that gets the engine close to its peak torque RPM at the preferred highway towing speed (typically around 65 mph). For most engines in the 250 to 350 ft lb range, that means using direct drive (OD off) on an automatic so the input/output is a 1:1 ratio...IOW 3rd on a 4 speed with OD transmission, 4th on a 5 speed with OD transmission. And that in turn means an engine RPM around 2500 to 3000.
  • Towing with the engine turning way below its peak torque RPM is indeed lugging it.
  • Having lots of low end torque means that downshifts to 2nd on a 4spd; 3rd on a 5spd can be avoided on grades of under about 5 or 6 percent. A downshift to 2nd or 3rd means engine RPM of 4000 or higher and that's neither comfortable to occupants nor good for the engine on a long term basis. Sure, on a long, steep, high altitude grade such a downshift is probably unavoidable and not harmful for a few miles. But having such downshifts on every slight incline is not good for the transmission.
I've spent the last year or so (and about $3000) improving my truck's low/midrange torque and ability to avoid downshifts to 2nd gear while towing on anything but the steepest and highest altitude mountain grades here in Colorado. I'm very happy with my results and feel the money was well spent. Keeping in mind that I'm towing at altitudes from 5000 to 12,000 feet, downshift frequency while towing has diminished from an almost-every-moderate-climb to just-the-seven-percent-and-up grades. Sure, I could have bought a more powerful truck to begin with...but none of them would fit in my garage. And none would have had Toyota's reputation for reliability.
Quote:
The only red flag Id have regarding some of the Jap/Euoropean peak-HP wonders involves turbocharging. Towing is murder on a turbocharged GASOLINE motor (diesel motors tow very well with turbocharging...). The problem involves heat generation and detonation, a devestating byproduct of high heat.
Heartily agree.
__________________
Ray

I use my TM as a base camp for hiking, kayaking, mountain biking, and climbing Colorado's 14ers


The Trailer: 2002 TM Model 2720SL ( Mods: Solar Panels (170 Watts), Dual T-105 Batteries, Electric Tongue Jack, Side AC, Programmable Thermostat, Doran TP Monitor System)

The Tow Vehicle: 2003 Toyota Tundra V8 SR5 4X4 w/Tow Package (Towing & Performance Mods: JBA Headers, Gibson Muffler, 4.30 gears, Michelin LTX M/S Tires, Prodigy Brake Controller, Transmission Temperature Gauge)


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Old 04-04-2005, 03:57 PM   #10
RockyMtnRay
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Default WDH or not?

Quote:
Originally Posted by sandy eggo
One big CAUTION if you want to tow with a BMW SUV. Unless they have changed their specs, you can tow 6000#'s with their BIG SUV, but the hitch weight can no exceed 600#'s. Thus if you have a trailer that needs a 15% tongue weight, you are really limited to a 4000# maximum trailer weight! I verified this with BMW. They say if you exceed that there is no warranty on related failures.

So, let's assume my hitch is rated for 600 lbs on the tongue. My new/next question is if the tongue weight (as specified on the TM website) of the 3124KB is 448, I should be fine; however, is that the tongue weight of a "dry" TM. What would the tongue weight need to be of a fully loaded 3124KB? And what are the safe tolerances for tongue weights - i.e., if the tongue weight is 600 lbs and the hitch is rated at 600 lbs, I'm assuming that this is not a safe scenario.

Thanks again for the help.

Rick
Generally there are two numbers provided for "allowable hitch weight"...one for a weight carrying hitch (aka standard drop hitch) and one for a weight distributing hitch (WDH). Typically you will have a much higher allowable weight with a WDH...on my truck the limit is 750 lbs (weight carrying) and 1100 lbs (weight distributing). You need to go sleuth out some more numbers....even call BMW if you have to...to find the allowed number for a WDH.

That being said, TM's tend to have very high tongue weights...typically 14 to 15 percent of total weight...because the axle(s) are further aft of their center of gravity than on most travel trailers. That aft location of the axle has the wonderful side benefit of making TMs inherently very sway resistant.

As for actual tongue weights on a heavily loaded 3023 or 3124KB, I'd estimate somewhere around 750 lbs (my very loaded 2720SL has a tongue weight of around 600 to 650 lbs). Sooooo, if the BMW limit is 600 lbs with a WDH, you're going to need to think smaller than a 3023 and/or going camping very lightly loaded. OTOH, if that number is for a weight carrying hitch, then you'll probably be fine with a heavily loaded 3023 as long as you use a properly adjusted WDH.
__________________
Ray

I use my TM as a base camp for hiking, kayaking, mountain biking, and climbing Colorado's 14ers


The Trailer: 2002 TM Model 2720SL ( Mods: Solar Panels (170 Watts), Dual T-105 Batteries, Electric Tongue Jack, Side AC, Programmable Thermostat, Doran TP Monitor System)

The Tow Vehicle: 2003 Toyota Tundra V8 SR5 4X4 w/Tow Package (Towing & Performance Mods: JBA Headers, Gibson Muffler, 4.30 gears, Michelin LTX M/S Tires, Prodigy Brake Controller, Transmission Temperature Gauge)


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