OFFDUTYEXPEDITOR

I finally got tired of the erratic shifting on my 1997 3500 cab/chassis. I really felt in my gut that it was my TPS according to what I had read on this site. I had a friend check it out with his digital volt meter. We could not get any reading at all. We took it off and drilled the 1/16 hole in the back and sprayed cleaner in it, let it dry, sealed the hole and remounted it and retested it. It started out at 1.729V but we were able to adjust it down to 1.648V. That is as low as we could get it to go. According to other posts it should not be any higher than 1.5V. The thing shifts like it has a brand new tranny. It had gotten so bad the last couple of days that I kept it under 50 mph because the shifting was so erratic. I guess if the TPS was dead that would probably cause that. Right now it appears as we have brought it back to life. My question is...is the TPS reading I am getting too high?? Will it cause any damage?? If so, any ideas on how to adjust this down any further.
Yes the two metal sleeves were removed. If I have actually fixed this thing without having to fork out $200+ for a plastic piece I will be overjoyed.
Thanks guys for the help.

OutlawStorm

I have mine set to 1.5 volts no problem with mine, but i do have an adjustable pot on mine so i can set it to whatever i like. I seriously doubt the voltage you have will do any probs,,, it may kick a code in the computer,, i believe the code is 24 TPS voltage to high or to low, but if you couldnt get a reading before, i am sure it already kicked the code. No big deal,, just get someone to erase it if it did. The nice thing i found with a higher idle setting,, it shifts later into overdrive now, before at 1.2 volts it would shift into OD at about 48 mph,, now at 1.5 volts its around 55 mph.

OFFDUTYEXPEDITOR

Yes I did notice OD kicks in alot later now (about 54mph). I also feel like the truck does not seem to immediately slow down by merely letting off of the accelerator requiring a tap of the brake. I can definitely live with that as long as it's not tearing anything up. By blowing a code does that mean my check engine light may come on? Sorry I am mechanically retarded.

kd460

I doubt you will get a code at all. You can remove the steel pressed in sleeves in the corners of the tps fwhere the bolts go for more adjustability.

Also, heres another tip. Take the transmission relay from your breaker/fuse box under the hood off your truck (the one for "transmission").

Remove that cube breaker, take the the cover off, you will see how the relay can be partially disassembled to get at the contacts, clean up those contacts with some fine (800 or finer) sandpaper, and use some contact cleaner and electrical friendly spray lube, shake excess off and put back together/reassemble.

If your 97 was anything like mine, the pitted and oxidized contacts can't be all that good for electrical transmission. It may be my imagination, but, I think my shifts are firmer, quicker. Wish I checked voltages before and after, but did not.

I ended up doing this with all my relays. Took one beer nd very little effort. KD

OutlawStorm

I think the reason it dont slow down right away is the convertor isnt unlocking right away, which i dont see a problem with it,, i hated mine unlocking the second you let off the pedal. Tapping the brake will unlock the convertor. I am not positive on the 97, but my 96 did not make the check engine light come on when i trip the code.

OFFDUTYEXPEDITOR

After driving the truck around for 75 miles and no recurrent shift problems I marked the truck back in-service with my dispatcher. At 2:30 I got a call to pick up a load to deliver to Windsor, Ontario. Before I could even pick the freight up the transmission went back to it's old ways. Anything above 55mph it felt like the torque converter was locking in and out. I went ahead and picked up the freight to get it out of the customer's face then passed it off to another truck/driver. I don't feel like it would have left me stranded but I hated the thought of driving 50 mph all the way there and back. This is getting quite old and frustrating. Luckily I am a full-time firefighter/paramedic and only rely on the truck for part-time income. I still feel like it is a TPS problem since it seemingly solved the problem for a short time and made a remarkable difference. Since I was getting absolutely no voltage reading before I cleaned it could it be the TPS is fried beyond repair and I should just go out and buy a new TPS? Did I mention that the tranny is a DaimlerChrysler rebuild that has approx 75,000 miles on it? I hate the thought of taking this to a dealer or transmission shop because they are generally lazy with diagnostics and just want to sell you a new transmission. I would think that even a DC transmission would last longer than 75K. Am I barking up the wrong tree? Does anyone know an honest transmission shop in the central Indiana area that are familiar with these trucks? Any advice would be greatly appreciated.

infidel

Just replace the TPS, they are availible at most autoparts.
I gave up on cleaning the TPS long ago, the results just weren't long lived enough to be worth the hassle.

OutlawStorm

Mine with the pot in it has now 228,000 miles on the original one, I to tried cleaning it once, never lasted long, but now since the pot on it, it has worked flawlessly. I still dont see how anyone can charge what they do for the TPS after seeing what is inside of them,, i would think that if they charged 40.00 for them , they would sell alot more as people would never even try to clean them

Sidewinder

I have to agree. I opened mine once, then again, then again to keep fixing the same problem. I then replaced it with a new one and no more problems.

OFFDUTYEXPEDITOR

Thanks guys. I finally bit the bullet and bought a new TPS. I got it at NAPA.
I had already looked up the price on the internet ($204) but when I went into the store I just acted like I didn't know anything about them and asked for one. When the guy pulled it up on the computer he gasped and said he couldn't believe they were charging that much and that he felt like they should wrap it in gold first. He had the manager come over to confirm the price and the mgr couldn't believe it either. The mgr told him to run it under someone's account since I was paying cash to get the wholesale price which ended up being $148.10 plus tax. Still too much but I was pleased to get the discount.
Knock on wood the truck is running perfectly. I wish I would have done this when it first started acting up.

OFFDUTYEXPEDITOR

I am drawing a blank. What is a pot? I know what a pos is : )

OutlawStorm

Its a potometer,,,, i use a 1,000 ohm adjustable one and have it hooked into the ground line, this way I can set my TPS to read whatever I want it,, no need to take the TPS off, and knock out the shims and oblong the holes. I can adjust it from under 1 volts to over 3 volts, it works great as I have control with it, I am now going to move the pot to the dash, so I can adjust it as I drive, Sure beats paying 150.00 for them,, considering i put 2 on my one truck in a year, and now since i use the pot, its been over 18 months and still working great

OFFDUTYEXPEDITOR

I am sure you guys are getting sick of hearing about my saga but just be glad you are not the one having to tell the story. : )
After changing the TPS the truck was running wonderfully. The first of last week I took a load from Indianapolis to Madison, IN about 90 miles. No problems. On Wednesday I picked up a load from Indianapolis going to Griffin, GA. When I got down to Nashville, TN on 65 I noticed my tachometer was doing strange things kind of jumping around. It appeared to be a bad reading because the engine itself was not surging or acting strange. I got down on 24 between Manchester and Chattanooga and the tachometer really went haywire, going clear up into the red zone and jumping back and forth. This started affecting the transmission and making it jump in and out whenever the tach was acting squirrelly. I found that if I drove under 45 mph it would not occur as often. I called dispatch just to see if they had another truck close but to no avail. I didn't really want to pass off the load and lose the revenue so I told dispatch I would continue but at a very slow pace. I drove the remaining 225 miles at 45 mph or less. I made the delivery and only 1 hour late. I decided I did not want to turn around and drive home 580 miles at 45 mph so I found the closest Dodge dealer (Speedway in Griffin) and asked them if they could take a look at it. They diagnosed it as a bad crankcase sensor and could have the part by that afternoon for $465 parts and labor. They said I would probably not make it home as it was so bad that all they had to do was touch the crank sensor and the truck would shut down. I got a hotel and slept while they fixed it. They also found a recall that had not been done involving the throttle linkage and repaired that for me. Then I get the call....they have also found that my fan clutch was allegedly seized up and they could fix it for an additional $277. I would have thought that I would have noticed that but not wanting to break down on my way home I told them to go ahead.
Whatever they did fixed the tach problem and transmission seems to be ok...for now.
Does this sound legit to any of you?
And to add to the stress, my accelerator stuck 3 times on the way home. Never an issue prior to having the recall done. Will another dealer look at that for me??

infidel

Sounds about par for the course.
Another dealer should fix the recall for free. Many times when they do the linkage recall they don't readjust the TPS, make sure they do.