Highlander chugging while towing?

[Padgett]

On a TLB in the hills of North Carolina I manually shift my GC but on the Interstate I just leave in Drive & maintains 2800-3000 rpm (4th unlocked of 5)) pulling a long grade at 65 with TM in back

Would be high rpms for a diesel but less than half way to redline with my V-6.

A lower gear that does not go into PE (Power enrichment usually about 50% throttle) will give better MPG with less strain than a higher gear that is lugging. Two things I monitor the most when towing are coolant/oil/trans temperatures (if boosted an EGT is more important but mine is NA) and the throttle position. AFR is good to monitor as well.

[klpauba]

EGT - Exhaust Gas Temperature
NA - Naturally Aspirated
AFR - ?????
TLB - ?????
GC - Grand Cherokee

Can you provide the translation for ?????'s? Thanks

[clan_salmons]

Originally Posted by klpauba

EGT - Exhaust Gas Temperature
NA - Naturally Aspirated
AFR - ?????
TLB - ?????
GC - Grand Cherokee

Can you provide the translation for ?????'s? Thanks

Thanks! You got two more than I did. I was wondering why his was "Not Applicable"

[oldstick]

Let's just make up something.

Tricky Little Backroad???
Air Force Regulations???

[Padgett]

Two Lane Blacktop (55 Chev was the same one in American Grafitti).
Air/Fuel Ratio

One of the hardest things I ever did was to get an Air Force Regulation changed (relating to Mil-Std-1750A)

[Shane826]

Exhaust Gas Temperature is not applicable on a Naturally Aspirated (NA, meaning not turbo- or super- charged). It's important on a turbocharged engine because the exhaust gasses are what spins the turbo. If it's too hot it will hear the intake air or possibly damage the turbo. On an NA engine it just flows out the exhaust pipe.

[gonzo628]

Originally Posted by klpauba

EGT - Exhaust Gas Temperature
NA - Naturally Aspirated
AFR - ?????
TLB - ?????
GC - Grand Cherokee

Can you provide the translation for ?????'s? Thanks

I think AFR is Air to Fuel Ratio.

[oldstick]

Originally Posted by Padgett

Two Lane Blacktop (55 Chev was the same one in American Grafitti).
Air/Fuel Ratio

One of the hardest things I ever did was to get an Air Force Regulation changed (relating to Mil-Std-1750A)

I should have known the AFR, but never would have guessed TLB.

Small world that someone else has even heard of MIL-STD-1750A, let alone familiar with it. That is the most common type of microprocessor I dealt with during my career, developing software with mixes of JOVIAL and 1750 assembly languages.

And yes, knowing how long and hard it was just to make a simple purchase of a single $500 software item, (proprietary to one vendor, no other competitors available) through the system, I can only imagine the arduous red tape involved in getting an AFR changed.

[LoveToCamp]

Padgett, my diesel rarely needs to rev to 2800 rpm, as it has the power to pull everything up the mountains at a lower rpm.

[Padgett]

first - the issue with low revving diesels vs a high revving gas engine (like my Pentastar) is gearing.

I suspect you have 420 lb-ft of torque at 2800rpm. My V6 has 90% of 260 lf-tt from 1800 to 6400 rpm. To equal your traction effort (force from tire to ground) I need to be turning 5,000 rpm - and still have another 1400 to redline.

Biggest advantage you have is boosted direct injection is about as efficient as you can get. But when you add boost and direct injection to a gas engine you can get the same efficiency on pump gas at a much lower initial cost and cost per mile.

I used to be a big fan of turbo diesels, my Vixen RV had one but wasn't available for my GC in '12 or would have ordered, but is nothing worse than a convert.

Second I used to think of a 1750A as a coprocessor in search of a processor. It could not address a byte so hard to send ASCII (e.g. use with a keyboard and monitor). Was supposed to be an airborne processor and Mil-Std-1862 was supposed to be the ground machine but 1862 was cancelled so all the AF had left was the 1750A & was speced in every contract. Took me two years but got approval to use a MicroVAX for ground test equipment (ATLAS based) instead. Major cost savings & boss made VP.