48RE and towing

[CLAYTON]

I recently had my whole transmission replaced and the service manager told me to never tow in over drive. Does anybody here tow in over drive? If I start to bog down i'll kick it out of OD but I don't see any reason to not have it in 4th on a flat road with RPMs over 2000. He said the 4th gear was not designed to tow. I'm sure there is some truth to this but I like to hear what you have to say.

 

[KBalzuweit]

Ignore what the idiot at the stealeeeer has to say. Call DTT or Suncoast and talk to them if you have questions. What does he think you are going to do run down the road @ 2800rpm in 3rd and get 7 mpg . I ran my 2nd gen as a hotshot rig and towed in OD ALL THE TIME. The problem I had was torque converter failure, if I knew how to help stop the problem from day 1 I would have never had a problem. One call to Stephan @ DTT he gave me some hints and suggestions and no more problems.

 

[robertyoke]

I tow all the time in O. D. just keep the revs above 1700 or so.

 

[CLAYTON]

03 ctd 4x4 HO 3500 QC SB 48re laramie graphite/slate 3. 73 stuff added = toy 491hp/1008tq

What do you have done to your truck... that is right about where I want to be with my HP and TQ

 

[Bertram65]

I tow in OD, but I have 4. 10s and stock tires, I do not tow in OD below 2000 RPM, for me 2000RPM is 65MPH, for you it is around 80MPH. I would tow in 3rd with your setup.

 

[SSage]

I tow in OD also, up to 14K in weight so far. I'm at 2000 to 2300 rpm while towing at 65 to 70 mph.



If you were stock, the trans would hold up. Its not made for the kind of power that comes from an "Edge EZ, Juice/Attitude". Upgrade the trans and have fun. I'm surprised you didn't have a problem with the dealer. Mine would have sent me on my way if they found any power mods.

 

[bmoeller]

If I had 3. 55's, I'd probably lock-out O/D. I have 4. 10's and don't lockout O/D unless I have to pull what is behind me, slow. Which in my case, is more often than not. Haven't towed with the new transmission yet.



The stock transmission I could slip pretty easy, even at stock power levels. Let alone, BOMBed. With triple disc T/C, Shouldn't be a problem.

 

[robertyoke]

What do you have done to your truck... that is right about where I want to be with my HP and TQ

ats vb/tc , dtt input for the trans, tst box with the old program, ats manifold, 4 inch pinnacle performance exhaust(jerry jardeen), direct mount b1, holley black pump with dd fuel line kit.
I think thats it. but it was not enough so truck is on the lift right now, most of its parts are done for twins b1/b2 . its alot of work to fab your own twins. .

 

[CPG]

Towing in OD with a trailer is common sense. With our 26' Alpenlite trailer we have always used OD on the flats, not lugging of course. When We come to the hills and grades, its out of OD.

Had well over 100,000 miles on my first Gen. with an Auto. Doing the same here with my 0-4 with the 48RE. Of course I am not overloaded here and lots of steep grades on our Sierra Nevada mountains out here. Just watch your "Tach" and you will be fine.



Chuck G

 

[CLAYTON]

Thats what I have been told... if it starts to lug take it out of OD. Just wanted to double check.

 

[Matt400]

I do but if I had your truck prolly wouldn't with 315's and those gears. My 33" tires are stretching it gear wise (for over drive use) for towing IMO.

 

[Warwagon]

Need quick term clarification. Lugging? What is it and is it some you can feel when it happens? I keep hearing the term but never had it explanned. Thanks for your time.

 

[CPG]

The term lugging is a term for working an engine under the impractical RPM's of efficiency. In other words, making it work too hard in a range that cuts down the good operation and making it harder. This puts undo stress on the engine.

One can feel this by sound and the vechicle's response being held back from operating at too little RPM.

This is what The Tachometer is for, to be a guideline for the proper RPM's under load under a given speed.

 

[Matt400]

Per Cummins it's (WOT) wide open throttle with RPM's below the max torque, 1600 I believe. With your auto you won't even be able to accomplish that as it will down shift before the engine see's a lugging condition.

 

[SSage]

Lugging an engine means putting the engine under heavy load by operating it at low rpm while the transmission is in a higher gear than needed to maintain proper rpm. Or staying in OD when you should be in forth, third or even second. Lugging can stress pistons, rings, etc and melt them due to the high EGT's.



If the engine can not increase rpm by throttle your lugging the engine if the rpm is low. So, your in 6th gear, the engine will not go above 1500 rpm or 1600 rpm with the pedal on the floor, the EGT will increase very quickly. The engine needs to stay above the peak torque with enough RPM to keep EGT in a safe range.



P. S. The 48RE will stay in OD a bit longer than I like on some hills. I find myself locking out OD to keep the rpms up. My auto will lug down to 1400 and stay there while loosing speed with the cruise on. I shift down at 1800 rpm on the highway. I like 2000 to 2100 rpm while pulling in OD.

 

[Fred Swanson]

CLAYTON, what was the outcome of the first transmission. Did the dealer break it open, or just stuff a reman in there? You will be back there again with a dead transmission. You should consider the upgrades. Less work is needed now than before.

 

[CLAYTON]

They completely took the whole transmission apart and replaced everything. I have a whole new aftermarket suncoast transmission at my finger tips I just need a few more bucks before I can get my hands on it. The new suncoast transmission has VB TC clutches input shaft and the works and should be able to hold what I need it to.

 

[SnoKing]

Maybe this was the problem. SNOKING

 

[Bertram65]

That post is a year old, if it is such a huge flaw you would think the problem would be more prevelent by now. Seems like a false alarm.

 

[SnoKing]

I was at DTT last Friday and asked Bill if they ever change that part. He said NO! The original truck in this post is a 2003 anyway. I know, you think DC is smarter than that. NOT! SNOKING