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overdrive only when truck is cold

5K views 25 replies 8 participants last post by  ohio hunter 
#1 ·
First my rant on this piece of junk cummins.Im about at my whits end with this thing. Currently I paid 8000$ for this truck with 142,000 miles, I spent 2000$ on the front end, spent 1200$ plus fluid cost to rebuild the trans 15,000 mile ago, then the overdrive goes out 3 monthes ago. Plus I had to pull the trans and reinstall. All these tranny guys are idiots, I cant belive no one can troubleshot this thing, they all want me to yank it out again, and it will be x amount to rebuild. Add in the "extras" I bought like ranch hands 2500$ and 4" lift 2000$, Iv put another 8000$ in this truck, plus killer dowell pin fix, sensor by radioter, heater core, fixed broken reverse lights, new alternator, 2 new batteries, starter. I couldnt even sell this for 8000$ right now with no overdrive, my wife is done with this thing, my brother in law is tired of working on it, and these 2 tranny guys dont want to answer my calls. Including the guy that rebuilt it, these guys just want to lay them on a bench and replace clutches.

If I go out and start truck, then drive down the road it shifts great into overdrive. After one or two cycles, of stopping and starting, it refuses to go into overdrive.c

So Im up to 500$ so far with this overdrive. 47 re 12 valve 1998
Here is what I have done

1) adjust tv cable, every which way possible, no fix, new tv cable, still no fix
2) checked on scan tool, fancy snap on thing at my nephews shop, no codes
3) put resistor thing from genos on wire off pcm to ground, nothing changes
3)check tps, all good 5 volts, then at idle 1.4 volts
4) drop pan,fluid good, hardly any shavings on magnet, idiot tranny guy comes to look at it with pan off,says replace speed sensor and neutral switch .
5)drive to tranny guys house, his fancy computer says tps voltage low, tps voltage high, buy new tps, bell crank, bushings, throttle rod ends. Set throttle rod for the 5" mark under truck, nothing changes. Now computer is cleared no codes for tps.
6) I cleaned all the body grounds today, nothing was really bad as I had
cleaned them a few monthes ago and repaired the ground under drivers battery.

Here is the trouble guide I always see posted and what I have done

.NO 3-4 UPSHIFT
1. O/D Switch In OFF Position. checked good to go
1. Turn control switch to ON position.checked good
2. Overdrive Circuit Fuse Blown. 2. Replace fuse. Determine why fuse failed and repair as necessary (i.e., shorts or grounds in circuit). where is this fuse at?? one under hood is good
3. O/D Switch Wire Shorted/Open Cut. 3. Check wires/connections with 12V test lamp and voltmeter. Repair damaged or loose wire/connection as necessary.checked good to go
4. Distance or Coolant Sensor Malfunction. 4. Check with DRB® scan tool and repair or replace as necessary.dont know where this is, ir what it is, but no compuer code for it
5. TPS Malfunction. 5. Check with DRB® scan tool and replace if necessary.fixed
6. Neutral Sense to PCM Wire Shorted/Cut. 6. Test switch/sensor as described in service section and replace if necessary. Engine no start.replaced, probably didnt need to truck started fine
7. PCM Malfunction. 7. Check with DRB® scan tool and replace if necessary.no code, doubt its pcm
8. Overdrive Solenoid Shorted/Open. 8. Replace solenoid if shorted or open and repair loose or damaged wires (DRB® scan tool).would this show up on scanner? where is this, is this the 2 pack under valve body
9. Solenoid Feed Orifice in Valve Body Blocked. 9. Remove, disassemble, and clean valve body thoroughly. Check feed orifice.
10. Overdrive Clutch Failed. 10. Disassemble overdrive and repair as needed.
11. Hydraulic Pressure Low. 11. Pressure test transmission to determine cause.
12. Valve Body Valve Stuck. 12. Repair stuck 3-4 shift valve, 3-4 timing valve.
13. O/D Piston Incorrect Spacer. 13. Remove unit, check end play and install correct spacer.
14. Overdrive Piston Seal Failure. 14. Replace both seals.
15. O/D Check Valve/Orifice Failed. 15. Check for free movement and secure assembly (in piston retainer). Check ball bleed orifice.

Any comments are appreciated:banghead::banghead:
 
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#3 ·
I love to hate it, if you know what I mean. Fought the steering for 3 monthes, 3 steering boxes later, and everything new finally fixed that, should of bought the borg to begin with.


But this tranny sucks, Iv got a bigger converter, all rebuilt, followed that trouble shooting, and still no overdrive. It was fine for a year then bam.

Gotte be something simple I am overlooking, works perfect when the truck is cold, as soon as that engine temp gage starts going up, no overdrive??
 
#4 ·
Nobody?

This trouble shoting link I see posted every where can anyone help me out with these things?

2. Overdrive Circuit Fuse Blown. 2. Replace fuse. Determine why fuse failed and repair as necessary (i.e., shorts or grounds in circuit). where is this fuse at?? one under hood is good

4. Distance or Coolant Sensor Malfunction. 4. Check with DRB® scan tool and repair or replace as necessary.dont know where this is, ir what it is, but no compuer code for it
 
#5 ·
Sorry I can't contribute anything useful to the tranny fix, but there are very good tranny shops out there. Relentlessly search for the best one in your area and go see them. It may be something very simple and cheap, or, like you say, another rebuild may be at hand.

Regarding the front end expense, KDP fix, various "things" that you have to fix after purchasing a Cummins - well, that's just the way it is. Every vehicle has several known weak points, and front ends, tranny, usually something vacuum related, and various electrical gremlins are all common with old trucks that have a 1,000 pound engine over a weak front end.

Get everything fixed, and you'll have a million mile, heavy duty truck that gets 20 mpg highway and sounds cooler than any gasser or even any other diesel.

If you want light duty, 17 mpg, but reliability foremost, get a Toyota Tundra. Every vehicle was designed by humans, and every vehicle will have its problems, including Tundras. Our trucks are unique, and nothing like them will ever roll off an assembly line again.

I'm a big fan of Japanese reliability, but my truck is so cool and easy to work on, I'll just keep replacing trans, T-case, injectors, ball joints, steering box, etc. when needed, as I would even on a Japanese truck with almost 500k miles.

Find an honest mechanic and transmission shop by asking around constantly.
 
#7 ·
Can I do that on a 1998 47 re? How do I do it, didnt have much luck on the search.

IM getting lock up, just not the overdrive. I havnt drove the truck long distance, besides down the road enough to warm it up when testing different things. Yesterday I unplugged all 3 pcm connections for 30 minutes, This morning I didnt warm the truck up at all, started it, let it run for 20 seconds with some light throttle, then hit the road. Shifted perfect, went 1 mile, turned left, jumped on the freeway, I have a 20 mile freeway drive to work, I got it into overdrive because it was still cold it worked. Im cruising along the engine temp gage starts going up, everything is good, hit 150, good, 160 good, about 165 on the engine temp gage, going a steady 65 mph, BAM out of no where it popped out of od, rpms jumped to 2300 or so and no overdrive.

I think tommorrow I am going to run to the bank in the truck in the morning, get it nice and warmed up, and come back and check the new TPS again, when the truck is nice and warm. Double check the voltage readings, I still have my old tps, if the readings are off, which they havent been since the new tps, maybe I will try the file trick on the old tps to get it into specks.

I also found where the coolant sensor is suppossed to be on the back top, I will check that to, and eliminate that. Im just convinced its not internal damage, or why would the truck get overdrive when cold? I havnt read anywhere on here with anyone else having those symptoms, just the older 12 valves with the opposite??

Sorry I can't contribute anything useful to the tranny fix, but there are very good tranny shops out there. Relentlessly search for the best one in your area and go see them. It may be something very simple and cheap, or, like you say, another rebuild may be at hand.

Regarding the front end expense, KDP fix, various "things" that you have to fix after purchasing a Cummins - well, that's just the way it is. Every vehicle has several known weak points, and front ends, tranny, usually something vacuum related, and various electrical gremlins are all common with old trucks that have a 1,000 pound engine over a weak front end.

Get everything fixed, and you'll have a million mile, heavy duty truck that gets 20 mpg highway and sounds cooler than any gasser or even any other diesel.

If you want light duty, 17 mpg, but reliability foremost, get a Toyota Tundra. Every vehicle was designed by humans, and every vehicle will have its problems, including Tundras. Our trucks are unique, and nothing like them will ever roll off an assembly line again.

I'm a big fan of Japanese reliability, but my truck is so cool and easy to work on, I'll just keep replacing trans, T-case, injectors, ball joints, steering box, etc. when needed, as I would even on a Japanese truck with almost 500k miles.

Find an honest mechanic and transmission shop by asking around constantly.
I know, I really love my truck, just not lately. The wifes durango,started knocking sunday bad, that 4.7 is gonna run me 1300$ for one with 108,000
on it, hers had 159,000, Im losing her, she is ready to go back to chevy.
 
#10 ·
Thanks 91 and ghost. I did order my service manual cd for 35$ from Genos last night when I got home from work. Man this thing is shifting great in the low gears, that new bellcrank made a huge difference, but this od is driving me crazy:doh:

My tps this morning was spot on 5 volts, at idle it was 1.5, I did get it turned down a little to 1.4, but no difference. At wot it was nice and smooth up to 4.2 volts.

I can not find that coolant sensor, I was reaching and feeling all over the place, would like to just eliminate that, or maybe get lucky and it happens to need a little push in. That thing is buried back there. I have attached a picture I found a vacume line back there behind my fuel filter deep in the engine compartment, looks like something is suppossed to be in there, but I dont see anything loose anywhere. I circled it in red, any ideas on that?

Thanks again Ghost I am going to pm you, my tranny plug has 8 wires going into the trans.
 

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#11 ·
One problem electronics can have is not being able to work when they get warm. For whatever reason electronics can stop functioning when they warm up. It was a common problem in the old days in televisions and radios when they were not all integrated circuits. Just because a cold electronic part works does not mean it is working when it gets warm. I would consider changing your transmission electronic parts although it is a shot in the dark.
 
#13 ·
I can do this pretty easy, but I believe my tc is locking up, will this help to detirmine something? Feels like I get drive no problem, then around 42-50 when it wants to go into overdrive, I feel the "shift" but it doesnt go into od, isnt that the tc locking up? I will try that now though, and let you know.

I got the wiring from ghostman, it looks like that number 6 connector on the trans plug is for overdrive, can I test that going down the road and see if I get a signal to that plug when overdrive should occur? If I run a wire from that to the cab, and put a test light on it, is this ok, and will it work?
 
#16 ·
Ok thanks guys. I made a quick switch from the link illflem posted. I just ran the wire through my passenger door. When I backed out the driveway, it was obvious the converter was locked, she stalled out when I put it in drive. I turned the tc off and ran down the road, as I got to 42 or so, she tried to go into OD but wouldnt.I felt it try and shift but just wouldnt go. I turned the tc on and the truck stayed locked in untill I turned the switch off.

Does this help us with anything? Its getting dark out now, and I have to work tonight, and in the morning, but tommorrow afternoon, should I try and check that number 6 pin on the trans??
 
#18 ·
Well I grounded out pin b21 on the middle pcm connecter, and no overdrive, pin b11 locked the converter, so I have to think the overdrive solonoid is bad or the wire is messed up in the trans. Will try that next and report back. Hopefully that fixes it.
 
#20 ·
The tranny guy that rebuild mine, is gonna do the solonoid pack, and "refresh" the valve body for 100$, plus parts. I have seen the you tube video of the guy taking the valve body out, but I just dont want to mess with it. It will probably be the standard solonoids. I dont have to much "extra" power on my truck, just what is in my signature, timing and the plate gone, but I really dont get on the truck to much. Every local guy jams the gas when they see me. Couldnt tell you what Tc I have, I know it was bigger and heavier then the stock one, when we put it back together. I will post back the results when its done, should be middle of next week.
 
#21 ·
I would upgrade to the borg warner solenoid. It is a lot better than the stock one. The price is not horrible either.
 
#22 ·
Thanks, I ordered this. Hopefully they ship pretty quick, tranny guy was talking maybe wednesday on doing this.

Hopefully yanking the wifes durango motor tonight, hoping for the best on that one, gonna try and rebuild if its not to bad, 50/50 from the way it sounds. If this week works out the way I hope, I will have both these vehicles 100% by the weekend.

I will post back when my truck is done the results.
 
#23 ·
:party018: Well it looks like the problem was the od solonoid. I just need to adjust the tv cable a little now for the early shifts, but od and lock up are great. I ended up getting that kit for 200$ from cascade and replaced all the electronics with the pan off, and put that borg sensor in.
Saturday I had to run down the road in the truck and I noticed just the MPH gage "jumping" up and down. The engine is reving High low high low, when I let off the gas and push the pedal its fine:confused013: I remember a few years ago I had a similar problem but worse it was the sensor on the front by the balancer had the wires "split" a little. What sensor would that be? Do you think that needs adjusted or checked again?
 
#24 ·
I think this is what you are referring to.

ESS. Check to see that the wire connectors are clean. One person used dielectric grease on the connections and that solved their problem.




Make sure the gap is correct.


Whenever you are trying to troubleshoot a problem ask what each problem has in common.
 
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#25 ·
Great, thanks for the pictures that's what I was talking about.

Whenever you are trying to troubleshoot a problem ask what each problem has in common.
Yesterday 06:25 AM
Do you think there is anything else that could be causing the truck to do that?

I remember I just taped the wires up and used a card before for the gap. I am going to clean that connector up and use the grease tonight, hopefully that solves this problem. Thanks again for the help, I will let you know how it goes, should be able to do this tonight. We got that new durango motor set last night, so I am on the home stretch of that project.
 
#26 ·
Just to finish this thread up in case someone reads this down the road. I had unhooked my noise isolater after the solonoid change to try and remove that last little "reving" I was getting.Well I went out Sunday morning and unhooked both battery negatives. I had my isolater about 3 inches up the apps wire, this time I moved it as close to the pcm plug as I could. Then I unplugged all 3 pcm plugs for about 45 minutes. Hooked everything back up and all is great now. I cant believe how good the truck is shifting now.:thumbsup:
 
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