For those with a DTT tranny: My truck has started locking/unlocking the TC a bunch, when just cruising down the highway. Thought it might be an issue with the DTT voltage regulator, and adjusted it down to 4.2 volts (from 4.46). The truck liked that for a couple hours, now it still does it, but kinda worse. Getting some 3rd gear start offs too. What else might cause it? Bad grounds in the engine compartment? Gotta be something simple. I hope anyway. Gonna have to make an appointment soon with Tim the Tranny Doctor.

 

You should have a noise blocker thing on there as well. That could cause it. Try wrapping the wire going from the alternator to the passenger battery with aluminum foil and see if that helps. I had to do that on mine.

 

Thanks Blue. I've been staring at my engine for the last 15 minutes hoping something would just be blatantly obvious. On that wire to the alternator, do you just wrap it around any part of the whole insulated wire, or on the end at the battery, or what? Don't want to fry something.

 

I wrapped it from the alternator to the battery and then taped it up with aluminum foil so it didn't look like I had aluminum foil wrapped around it.

 

Could your transmission be kicking out of OD going down the highway? With the cruise on, try tapping on the brake pedal and see if this is similar to what you are experiencing. I had this problem going down the highway and it turned out when I'd hit a bump my brake pedal would loose contact with the brake switch and kick it out of OD and then after a ways it would go back into OD. I thought something was slipping, but it is normal behavior when the brake pedal is applied. It just took a small switch adjustment to fix.

I had one 3rd gear start after my DTT was installed and an adjustment of one tenth of a volt by the builder took care of it. The DTT voltage regulator is very sensitive to adjustment and too far either way can cause problems.

Good luck getting it ironed out. I couldn't be happier with my new trans after getting those two things taken care of.

 

I know what you're saying about the brake pedal, don't think that's it though. I'll hold the brake up with my toe and see if it still kicks out, I think it will though. I probably adjusted the voltage too far down, maybe should try 4.3 volts. I'll try that, with my new customized alternator wire, and see what happens.

 

If that doesn't work...call and bug Tim...he likes it

I think you've got all the simple stuff covered for now!
Chris

 

Did you solder the connections for the voltage regulator, if you used the scotch locks that is most likely your problem.

 

Probably have the scotch locks. I'll have to take the truck in for a checkup here soon, I hate to pester Tim about it on the phone. I'll look at the connections this morning. Thanks.

 

Hey Blue, I think your tinfoil trick fixed it. Truck didn't act up at all today, for the first time in a couple weeks. Buys me some time til I can get it in for its physical. Thanks a lot, this website is awesome.

 

I have a DTT trans and mine started to do this and it was my throttle position sensor. I think it was $175 or something like that

1997 CTD 2500 4X4 ex-cab long box 235,000, gear vendors 8 speed , stage 5 TST fuel plate, 4" exhaust, 370 injectors, full DTT trans, turbo silencer MIA, X-monitor, 4:10 gears w/limited slip, new style tow mirrors, stock turbo and pump

2004.5 CTD HO 2500 4X4 4 door long box, stock for now