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bowler1's avatar
bowler1
Explorer
Jul 21, 2014

Towing in the mountains with a gasser????

I recently upgraded from a pop up to a travel trailer that is 5000 pounds dry. Also got a new truck...2012 Toyota Tundra.

Today i towed through some pretty steep mountains. I locked out ovrrdrive so was generally in fourth and i had a full water tank.

On some steep hills on highway i had to downshift to third to stay above 60. The truckpulled great but reved pretty high. On some backroads i had to shift into second to stay above 45. Again it reved high into the 4500 rpm range.

My question...it certainly didnt sound good for the truck but i imagine its ok. The engine and trans temp were fine. Is this better than keeping it in the higher gear?

What would cause greater wear and heat for tranny higher or lower gear in this instance?

The engine was starting to struggle in the higher gear but really screaming in the lower.

I suspect from the posts i have read that the lower gear and higher rpm is fine and probably better than struggling in a higher gear but it certainly didnt sound good
  • What will contribute most to transmission getting too hot? Shifting a lot? Running to high a gear? The hi rpms?
  • Like said, high rpms are fine with a gasser. Most torque is generally found in the 4000 rpm range. The main concern I have on hills is transmission temp. If you don't have a digital temperature gauge, get one.
    Best not to let transmission temp go above 220f.
  • Sounds like it handled it fine. I towed a lot with a gas truck. Never thought I "needed" a diesel.
    Now that I have a duramax/allison truck, I'll never buy another gas truck, and I'll never buy a truck without an allison automatic unless I buy a manual trans.
  • Don't worry about revving your 5.7 at 4500 RPM. That engine can handle the higher RPM as it is designed to do just that. It's redlined at 6000 RPM.
  • Those gasser engines will rev all day long. So much better to rev than to lug the engine in a higher gear. And as long as the trans torque converter locks up it is good, too.

    That being said, when I towed heavy and up hill with my gasser, I would let it shift where it needed to be. But would keep the rev's at about 4000 max. Didn't care what the speed was. Or the gear. Pull up the hill at 4,000 RPM. Maybe it was 3rd gear at 45 MPH. Or 2nd gear at 30 MPH. But at those engine speeds the engine and transmission were happy at 4000 RPM. Don't worry about those trailing behind you. They know you and your tow vehicle are the best you can.
  • I'd pull the grades in 2nd gear going around 50-55 mph pulling around 3500 rpms with my old 97 F150 with a 5.4 and 3.55 gears towing a #5000 TT.. Worked for me...

    I could have gone 60-65-70 if I wanted to.... I just didn't want to.. ;)

    My rpms would have risen for each speed increase...

    Traded that 97 with over 255,000 miles on it too and still running fine... :)

    Now I tow the same grades, towing the same TT at 60-65 mph pulling around 2500-2800 rpms in 4th gear with the new Eco... :) :)...

    Love my Eco.. :)

    Mitch
  • Yep, lower gear and higher RPM. I went through the WV Turnpike southbound and at times my truck would drop down to 55 in 3rd gear, a little more throttle and it dropped to 2nd and pulled hard back up to speed (around 4500 rpm at 65 mph) never once did it complain. definitely let it rev instead of bog down! trans temp never got over 190deg.

    And you weren`t struggling. the Toyota was operating the way it was supposed to. Diesels rev the same way, except their redline is around 3500rpm. so when they are spinning at 2500 rpm they are working hard!
  • You did it the right way. Gassers make their power in the higher rpm's. That's one of the reasons some folks prefer diesels.
  • Lower gear, higher RPM preferred both going up and down.

    Engines and trannys these days are all computer controlled and will protect them.
  • Lugging the engine could be bad. Slow down. Let traffic pass you. With my diesel truck I do the speed limit only.