With my auto tranny while I'm pulling a load anywhere from 5k to 18k should I turn off my O/D? I have added a Power puck to the truck 55 hp and 150 torque so this helps the truck not to down shift out of O/D. The truck might jump out of O/D once maybe twice on a 2 hour drive. Am I wrong to pull loads in over drive? I live in very flat country so hills aren't a factor.

 

I use OD only if I can keep my RPM's above 1800. Otherwise I keep it in 3rd gear and let the RPM's get up to 2400-2600.

My $.02

 

I have always towed in OD if I can keep the rpms up. I had a 96 (about 130,000 to 140,000 miles) truck with shift kit before this one and traded it in on the truck I have now. I towed in OD with it and it was still pulling well when I traded it in. I have just upgraded this trany to a full Suncoast unit and I tow in OD with more confidence than before. I will say that gauges are a must to keep an eye on everything. Your exhaust temps will also dictate when you need to drop out of OD.
Hope this helps.

 

I'd say stay out of OD until about 60mph.

 

I have been towing in OD but I also have 4.10 gear so once I get to the open road into OD. around town I take it out of OD.

 

I leave it in OD towing or not the tranny knows when to downshift or upshift....I will disengage OD if the torque converter starts to lock and unlock (hunting).....we baby these trucks too much....if you break you truck then you don't need to guess about what will happen next

The tranny is a known weak point but normally only if you increase HP or tow something it wasn't built to tow....my truck gets worked hard to make a livin for me I have pulled 30000 GVW and done it safely without problems....gages to watch temps are important including a tranny temp gage

 

This thread is fairly recent and almost identical to yours:

https://www.dieseltruckresource.com/...threadid=37540

 

Thanks for yalls info. I pulled a trailor today and ran in OD the whole time I guess I will run it till it brakes

Thanks agin.

 

I tow in OD all the time on flat land. I turn on my DTT Smart Box and it keeps the tranny in 3rd until 57 mph where my RPM and Torque is high enough to get good efficency. I try to forcast when the tranny is getting ready to shift out of OD and then do it manually. I use the EGT and Boost to help predict when to shift out of OD.

 

Yeah I need some gauges but I'm going to wait until my warranty is out. Just another 14k to go THEN MAJOR BOMBING IS GOING TO HAPPEN