When I'm driving over 40 mph the tranny won't shift out of overdrive when I mash the throttle. Is this normal? Is there a way the linkage can be adjusted to allow it to shift down? It's really a pain to have to reach down and hit the OD to lock it out.

Thanks for any suggestions

 

Old man;
The factory manual says to adj. the kickdown. Loosen the camlock on the cable housing right behind the metal bracket it's mounted in, stick a 3/16 drill bit in the elongated slot of the likage, between end of the linkage and the stop pin it contacts. Be sure and lock the camlock again. Hopefully this isn't totally confusuing. ??? It's probably is easer to print this and read it while looking at the linkage.

ramguy

 

The problem is most likely in the Throttle Position Sensor (TPS). It's the little square box that sits on top of the injecton pump. It is the source of countless headaches and hours of cursing. If you do a search here, you'll probably dig up a good lot of info on it. If not, I think there's a certain church-going-black-truck-driving-stick-wielding Canadian somewhere in here that can help ya out ;D :P ;D

Cheers,
Sean

 

Ahhhhhh crap...... my cover is blown............. ;D

Pastor Bob.

 

 

Old Man,

I have a "how to" for the TPS adjustment. The TPS is the most common source of 3-4, 4-3 shift problems, though not the only thing.
I'd have a try at tweaking the TPS before doing anything else.
The kickdown cable or 'throttle valve cable' is primarily related to the 1-2-3, 3-2-1 shift pattern.
Try a search for "TPS ADJUSTMENT". If you can't find it I'll be glad to email the entire text file as it's the same as the one I posted on this board.

Pastor Bob.

 

Hey, everbody, I appreciate your suggestions. Right after I posted this the darned thing seemed to work properly. I was going to "test" it again Thursday but, would you believe it, it was raining in Seattle. I'm a wimp and don't like to screw around on slick roads. Looks good out today so it'll be a good time to try again.

The Old Man

 

Okay, here's my story and I'm stickin' to it. Just got back from a 1,000 mile trip going over Cascade's and Blues. Had a 3,000+# cab over camper on it. :P Overdrive worked just fine.

This was also the first trip with gauges. What a difference being able to see what's going on rather than just guessing. Turns out I too easy on it before when pulling hills. This time just watched the EGT and tranny temps. Didn't let the EGT get over 850*. Gotta admit the pyro is post turbo. I'm a wimp and was afraid to drill for a pre turbo install and the PacBrake already had a plug for it. The probe for the tranny gauge is in the pan. (One out of two isn't that bad). Locked out the overdrive when pulling the hills but let it run free when on the flat. The tranny temp never got over 180. In fact, most of the time it ran at 150*.

Oh yeah - - milage for the trip was right at 14mpg.