Engine/Transmission (1994 - 1998) No OD after Throttle Recall

[MASanders]

So I finally brought my '97 3/4 Ton 4X4 (166,000 miles) in to the dealer for the sticky throttle recall. My truck had been sitting for about 6 months, so by now it was really bad. The transmission had never been touched, except for a couple of fluid changes (I've had it since new). I know the transmission is getting tired, as it hits the 2-3 shift pretty hard, and sometimes flares a little between shifts.



Anyway, when I get the truck back from the dealer, it won't engage OverDrive (lock-up). I have a Snap-On scan tool, so I can see that it engages all 4 gears. The OD always shows "released". I brought it back to the dealer, and we both figured the throttle wasn't adjusted right. They checked, and said that the TV cable was in bad shape. It was rusty and had water coming out of it (Although I'm a mechanic by training, I haven't wrenched in a while. I'm also not familiar with what's on this truck, and haven't crawled underneath yet. ). Sounded reasonable to me, I live in MN, & things get rusty. They said if I'd pay for the cable, they'd through it on for free.



Today, they put the TV cable on. Then, they called and said that the truck still wasn't engaging the OD. I wasn't going to argue at this point, and of course they said it was just a coincidence that it happened when I brought it in. I didn't mention that I have wrenched at dealers, and was a Service Manager for years. (By the way, I didn't have to pay for the cable at this point, either. )



Sorry for the lengthy explanation, but it has to be something simple. I'm a "foreign car" guy. I'm sure I could spend a bunch of time and figure things out, but my experience says that someone here knows exactly what's up. I'm aware that the transmission ultimately needs a rebuild, but if I could a little more out of this one, it'd be great. It's basically OK in town, I just can't drive over about 55 mph.



THANKS!

 

[HLEschenko]

If the truck was mine, I'd drop the transmission pan, inspect the filter (look for clutch fibers), adjust the clutches and reassemble with new oil and filter. That should give a starting point for troubleshooting the OD problem.



Of course, driving habits maybe a reason for a rebuild. If the truck is lugged regularly, the transmission maybe on its last legs. The OD button on mine is on up to 55mph with no tow and 60 mph when towing a 5K camper. The torque of the engine is hard on the clutches at low RPM.



I know know mine needs adjusting when it shifts hard from one gear to another .

Good luck.

 

[Bob4x4]

If it was ok before the recall and not now... ... ... ... . ck the tps,the voltage should be set at 1. 0v. I prefer about 1. 02.



Bob

 

[Howard Durand]

Make sure the TPS is rotating when the throttle is being advanced and if the cable is attached. Also check that the OD/TC control wiring is connected at the transmission.

They did something at the shop that is preventing the shift to OD. I am not familiar with TPS operation in the later years but I also believe one of the relays in the power distribution center is involved.