• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

1994 Chevy Cheyenne 2500

N

NASIMMONS

New Member
Messages
6
Reaction score
5
A while back a bought a 1994 Chevy c2500 the transmission was good would shift fine never did anything wrong. One day I drove to dmv and I went to back out and it wouldn’t reverse so I stopped checked the transmission fluid it was dark but not black and it was full so I kept going I had stuff to do so I was on the way back and then it wouldn’t go into 3rd, then 2nd, and then 1st stopped working. Now if it sits for a while it will go into reverse or first and will drive for roughly a minute then will go completely out. Would love to get some insight on what it could be (never seen it go out like this before) if it’s as simple as fluid and filter swap or if I need rebuild/swap transmission
 
Welcome to thetruckstop.
I dont know a lot about transmissions but to Me, it sounds like is might be transmission time.
You might rent/borrow a transmission pressure test gauge from a parts store, hook it up and see what the pressures is doing.
Oriellys here does rent/loan tools. The rent system is, You lay down the money for the tools, then, upon returning the tools, you get a 100% refund.
 
Classic low fluid symptoms. With engine running recheck the fluid level after 1 min. Likely dump 1/2 to 1 quart in it... Because the transfer case oil seal is likely bad and the trans oil gets pushed into the transfer case. You are a 2WD ... Then may have leaked out.

Pull codes as transmission is an engine and will not trip the SES light.

Is the electrical plug covered in oil? It make need to be cleaned out as oil is an insulator.

I get the trans rebuilt in/out for like $1100 plus hard parts like gears. Not worth screwing around swapping for used junk that may or may not work with said specific year.
 
Sounds to me like the filter seal cracked which was a common problem on the early seals. The seal cracks, and as the fluid thins out from warming up, it begins to suck air instead of fluid. The problem is, if you run it until it starts slipping, you toast the trans.
 
How many miles on pickup/tranny? My '94 C2500 did something similar at 165,000 miles. About 3 weeks after I had bought it used out of Houston and drove it back up to Nebraska this happened. Went to back out of a parking space, as I dropped it into R and started to pull out felt a small lurch but rolled on out as it was slightly downhill. Dropped it into OD and pulled away. Then the fun began out on the street. It wouldn't shift up into 3 or OD while driving, nor did it have Reverse, either, when stopped. Did fluid check, full and bright cherry red. Took it to reputable local transmission shop that does a lot of commercial/fleet servicing/repair work. Come to find out three things that the guy I bought the truck from had done.

1st, the ECM had gone bad, which goes to default mode and puts the transmission into maximum line pressure.

2nd, the P.O. pulled the SES light bulb from the instrument cluster to make it "go out" because it was cheaper than replacing the bad ECM, so transmission shop replaced the SES bulb so they could read the DTC's and discovered the dreaded "death code" for the ECM.

3rd, I was damn lucky on that 1,000 mile drive back up from Houston as going to maximum line pressure caused the face of the Reverse apply piston to blow out when I put it into Reverse. That causes no line pressure from the now huge internal leak for the 3rd/OD apply pistons to work.

So, a new ECM and a lifetime ownership warranty rebuild on the 4L80E with improved/updated/HD parts/clutches/steels and I was back out on the road with a tranny BETTER than stock off the factory assembly line.

The stock phenolitic plastic apply pistons are a know weak point of early 4L80E transmissions, as is the single Reverse band anchor point breaking off the inside of the transmission case (pray that didn't happen, new case is that fix) until the '96 upgrade went to a two anchor point Reverse band with two anchors cast into the transmission case.
 
Husker6.5 said:
How many miles on pickup/tranny? My '94 C2500 did something similar at 165,000 miles. About 3 weeks after I had bought it used out of Houston and drove it back up to Nebraska this happened. Went to back out of a parking space, as I dropped it into R and started to pull out felt a small lurch but rolled on out as it was slightly downhill. Dropped it into OD and pulled away. Then the fun began out on the street. It wouldn't shift up into 3 or OD while driving, nor did it have Reverse, either, when stopped. Did fluid check, full and bright cherry red. Took it to reputable local transmission shop that does a lot of commercial/fleet servicing/repair work. Come to find out three things that the guy I bought the truck from had done.

1st, the ECM had gone bad, which goes to default mode and puts the transmission into maximum line pressure.

2nd, the P.O. pulled the SES light bulb from the instrument cluster to make it "go out" because it was cheaper than replacing the bad ECM, so transmission shop replaced the SES bulb so they could read the DTC's and discovered the dreaded "death code" for the ECM.

3rd, I was damn lucky on that 1,000 mile drive back up from Houston as going to maximum line pressure caused the face of the Reverse apply piston to blow out when I put it into Reverse. That causes no line pressure from the now huge internal leak for the 3rd/OD apply pistons to work.

So, a new ECM and a lifetime ownership warranty rebuild on the 4L80E with improved/updated/HD parts/clutches/steels and I was back out on the road with a tranny BETTER than stock off the factory assembly line.

The stock phenolitic plastic apply pistons are a know weak point of early 4L80E transmissions, as is the single Reverse band anchor point breaking off the inside of the transmission case (pray that didn't happen, new case is that fix) until the '96 upgrade went to a two anchor point Reverse band with two anchors cast into the transmission case.
Click to expand...
Thanks man I figured it was caused by ecm and now other thing are probably wrong. How much did you pay for rebuild with upgraded parts?
 
MrMarty51 said:
How much was the bill on the OH of the transmission ?
If You dont mind telling.
Click to expand...
NASIMMONS said:
Thanks man I figured it was caused by ecm and now other thing are probably wrong. How much did you pay for rebuild with upgraded parts?
Click to expand...
Ok, this was back in 2001, so we're talking 2001 prices. Here goes, prepare for the ride along.

The new ECM was a '94 only specific code for C&C (Cab & Chassis) upfitter Commercial HD C2500 with a built in speed-limiter (82mph) in the PROM chip. Local (as far away as KCMO) GM dealers didn't carry that coded ECM, had to be special ordered in from a warehouse out in SoCal. That was four days wait right there, after they had replaced the SES bulb to retrive the OBD-1 DTCs to tell that the ECM was dead (along with other issues), just so they could install it! There was the labor for diagnosing and replacing the removed SES bulb (had them do all dash/idiot bulbs while they were in there) replace the early '94 2-sender TPPS pedal assembly with the late '94 3-sender TPPS pedal assembly so it could talk to the new ECM (and also NOT go into the engine runaway scenario the early units would put 94s into that necessitated the factory shutting down the production line to sort out why they were running away). The transmission was totally rebuilt/remanufactured from the torque converter (upgraded HD friction, lock-up piston assy, 200 rpm lower stall) to the rear seal. New, up graded pump, all new HD Borg-Warner gray frictions and steels in the clutch packs with more than stock where possible. Kevlar reverse band. Upgraded HD forged steel forward drum hub, 34 sprag HD roller clutch. Billet steel apply pistons. Sonax check ball/seat repair/upgrade kit and valve/bore repair/upgrade kits for valve body along with a Transgo Stage 2 valvebody kit. All thrust washers replaced with thrust bearings where possible. All new bushings, bearings, gear assys, gaskets/rubbers/seals. All new solenoids/harnesses and sensors/senders. Derale 4qt pan w/magnetic drain plug. Dexron III transmission fluid. Lifetime warranty on parts and labor if transmission fluid changed every 30K (by them or any ASE shop w/receipt).

All said and done with everything set me back $3200.

That transmission was RPG proof! I towed a 24' dovetail trailer with a Bobcat 755 and a full pallet load of 60# Quickcrete sacks behind it and a full load of new windows, doors, and materials in addition to the normal tools/equipment load to put the truck at about 10,800 gross plus trailer weight (about another 10K) inside Omaha up and down those hills on city streets. Being among the hills/bluffs of the Missouri River, think San Fransisco/Seattle for hilliness/steepness. I never had any transmission issues/doubts of capability the next 70k miles with it, no matter what I put it through. What finally killed Old Blue the Money Maker was cracking both heads one February day up in Omaha heading back to Lincoln with an empty truck.
 
That to me seems to he a very fair price for all that You had done. I do realize though, that todays money it would probably be close to the $5000.00 mark.
So just the transmission with all that You had done to that one would be probably less than 4 thousand. Still a good deal.
 
Yeah, there was a lot of racing/HD TH400 stuff done to the main part of the transmission and the fixes/upgrades available at that time for the OD section/lock-up converter, which still are the weak spots of the 4L85E.
 
You must log in or register to reply here.
Back
Top