2nd Gen Non-Engine/Transmission Auto trans question

[Cobra]

I posted this question on the towing and hauling but it never came up so I am trying it here. I know this is the wrong forum.



My neighbor bought a 1995 RAM 3500 cummins with an auto trans. He pulls a 5er that weighs 8,000. Should he shift the gears manually from 1 to 2 to D, or just leave it in Drive. Also, the truck has overdirve. Can he use that when towing or not.

 

[rweis]

I'm NEW to diesels, but I read that you do not want to use OD unless you can keep the rpm's in the 2000+ range. I think it is so you are developing enough torque an are keeping the fluids flowing at a pretty good clip through the transmission / transmission cooler.



A lot of the post have guys towing much heavier than 8k at 75+ in all types of terrain. My 5er weighs in right at 8k and I generally run it 70 on the Interstate (in the right lane of course) not in OD. The engine revs a little, but has good response torque and the fluid flow through the radiator and transmission would have to be pretty good.



I think the key is keeping the engine from lugging which as I read it is fairly stressful to the engine and transmission.



Hope this helps



Bob Weis

 

[BFC]

I tow a 9K fiver and I leave it on "D" from the get go. Depending on terrain, I'll tow in OD or not. Tell him to keep the RPM's above 2000 and he'll be fine.



That was before my transmission upgrades. I'll get to try the new set up over new years, will see how it tows with the DTT stuff in it. Should be fun.



Glenn

 

[Blakers]

I don't believe running over 2000 rpm is necessarily reducing strain on the engine - 1600-1800 is real comfortable on them - especially the 12 valvers.



Towing in overdrive out on the highway should be fine for the engine. The advice of towing with OD locked out is most likely if you have a weak (stock) transmission and a BOMBed engine. The engine's torque will simply slip the heck out of your torque converter clutch and burn it up, sending debris throughout the transmission.



Blake

 

[Extreme1]

What Blakers said!

Also, the 24 valve engines run more efficiently above 2000 RPM. The peak milage on a 12 valve is at 1500 RPM. I would tell him to keep it above 1500, no OD = long trip!