auto trans mods for towing?

[TRoe]

Hi guys,

I am a 2nd gen (NV4500) guy but am here on behalf of a 3rd gen (auto) guy I know. He has an 04 (I think) 3500 QC SRW 4x4 that is bone stock and about 150k kms (~100k miles). Having recently purchased a toy hauler (10k lbs GVW), he is wondering what to do, if anything for his trans. First thing I suggested was a temp guage. The truck has been babied and will continue to be, and the towing will be through some mild mountain stuff (SW British Columbia to the interior/ think Seattle and heading east for you Americans).
What does he:
1. have to do?
2. should do?
3. do assuming funds are not too much of an issue?
and for all these questions, what should he expect for cost?

TIA
Tim

 

[RSlater]

I would recommend installing a DD pan. Lowers trans temps significantly due to increased fluid capacity and cooling fins, thus minimizing the wear due to excess heat. As an extra benefit, the Mag Hytec pans provide ports for a temp probe and a drain plug to ease fluid changes. Unless the engine is modded (putting extra stress on the transmission), I haven't experienced any problems towing up to 10K, but I've only got 50k on my rig. Just my 02 cents...

 

[p-Bar]

Agree with Rslater down the line when he needs a rebuild use the upgraded valvebody and torque converter (weaklink) . I would just run till it brakes.

 

[jelag]

My BIL has an auto that did start to give him an overheat problem and he added the Mag Hytec pan... that lowered the temp for sure... . he full time RV's with a trailer that weighs 16K lbs. . he's added an exhaust brake and services the transmission every 50K miles... to date he's at 175K miles with no problems...

On most of the straight and level highways he's running the truck and trailer at 65 in OD but once he gets to the hills, he's got it in tow haul and uses tow haul when going down hills with the exhaust brake...

 

[cerberusiam]

Shift kit at a minimum. That will fix the circulate in park issue and then the drain back valve can be removed for better circulation thru the cooler. Those 2 mods will do the most to prolong the trans life.



With a shift kit highly recommend a billet front band strut and anchor so 2nd gear apply will work consistently and not break the cheap stock stuff with the extra pressure. Also, a billet front servo cover to minimize leakge that is an issue in that area.



Next step up would be a good TC to better use the power and help with towing. At that time pulling the pump to replace the reaction rings is recommended, and, might as well pull the direct and forward drums to freshen them up and possibly add another clutch to the direct pack if so desired.



A trans temp gauge in the front cooler line, hot line, is going to give the best overall measurement of temps and when to downshift on steep grades or stop and go traffic. A deep pan is nice but extraneous for what he is doing. The factory pan and system alreayd holds 4 gallons, fix the issues that normally hinder cooling and the OE cooler along with the factory fill is entirely adequate to keep the fluid in its operating range.



The idea is to keep the bands and clutches from slipping under a load, the shifts positive and firm, the TC clutch solidly locked when needed, and the fluid temp 140-230 degrees. Changing fluid at recommended intervals plus the above will make the trans as bullet proof as possible.



The biggest caeveat to fixing all the little issues mentioned and NOT replacing the TC with a billet cover one is the tendency for the stocker to ballon the cover under loads. The 48RE is much better in this area but it can still be an issue if one is unaware of possibilities. Recommend periodically checking the flex plate to TC bolts to make sure they stay tight. Depending on load, power output, driving style, etc, they can loosen on the stock TC due to lack of support in the cover. If at any time a shudder is noticed while TC is locked its replacement time, but, depending on other variables that may not ever happen.

 

[ray1933]

Auto tran updates

As you can see by my signature block I'm running the same transmission he is and all I have done is install the extra deep pan. I have hauled a 10. 5 PU camper, pulled a 29 foot 5th wheel, and now have a 9. 5 Artic Fox w/slide and pull our boat. I have no gauges like some folks do but pull at 65 to 70 in overdrive on interstates and turn it off when I'm the mountains. So far so good.