I have a 1998 Blazer 4wd 4dr w/ the 4l60e tranny. one day on my way back from visiting family 4 hrs away, my transmission started slipping real bad. eventually it would only not slip in 1st and 2nd gear so i had to drive the final 120 miles home in 2nd gear. Ended up being a burnt up 3/4 clutch. i guess a check ball embedded itself in seperator plate, ect. But anyway, to make a long story short, rebuilt transmission , ended up with no reverse. so took it back out, relaced few more things like drive shell, forward accumulator, speed sensors, shift solenoids, ect. put it back together, now nothing.....wont go into any gear. Any ideas? Desperate. Thanks

 

Did you personally rebuild this transmission or have a shop or friend do it? Seems like you may need a better game plan before you keep throwing more parts and money at it.

 

If a shop did the rebuild, they should be held to a certain standard in regard to the quality of their work. My tranny's acting up (posted in the previous thread), not sure if it's electronic or mechanical yet, but I'm skeptical when a mechanic claims a rebuild is the fix-all of things. I've heard of too many of these tranny's getting rebuilt, only to dish out the same or worse symptoms afterwards. Heard one case where a guy had his rebuilt, and later on it turned out to be a blown fuse.

 

Amen to that. I have had the OBD2 code "P0700" (Trans Syst Malfunction) forever on my 96. Nobody I knew or talked to could offer any possible causes. I know a guy that works for a Trans shop and he said it could be a million things. 2 weeks ago it stated to slip when I put my foot into it. Then, just as quick as a blown fuse; it was slipping in all gears and reverse worked only when it was cold.

Nobody around here has any "work around" repair ideas; but they all say a rebuild is a surefire solution ?! My RPO Code (M30) is for : TRANSMISSION,AUTOMATIC 4 SPEED,4L60E,ELECTRONIC 4-SPD A/TRANS(M30)

My little truck is parked awaiting a cost effective solution. I am anxious to see how this thread fares.

 

I assume you got the gear selector cable in correctly; I know it is easy to put the pump in backwards as it fits either way, but only works in one. Found that out the hard way when I installed a shift kit on my ole '95 Blazer.

 

The P0700 is a generic code that is set when the computer senses a component slip or a problem with input/output electric signals. The 1996 is the first presentation of OBD2 and the protocols and code definitions have changed so much over the years. The thing with codes that set MIL/check engine light can really send you down the wrong road when you plug in a "code reader" vs a OEM supported "scanner" a lot of times the code reader will give out several codes so you go buy a bunch of parts. Put the said parts on maybe its fixed maybe not fixed, maybe worse! A lot of codes that are set are "piggyback codes" that are set after the initial trouble code is set and you need to test those systems before condemning them. The automotive service industry has changed dramatically over my 40 years in it. New techs have to be electronic savvy plus still getting their hands dirty. You also MUST keep up on current information as things change overnight. The internet has provided a huge help in people interacting on issues that they have had in a matter of minutes were as in the old days it was the trickle down effect from local dealership techs that would see the problems first and then share the information if they wanted. Kinda closed mouth at the time as the dealers wanted to be the go to shops. But back to the issue of the transmission slipping. The unit has to come out and be repaired or rebuilt. At one point you might have been able to repair some issues without having to remove the transmission.

 

* To the OP, you have created 4 different threads concerning this transmission's problems. Please keep all posts within this thread so everybody can follow the progress of the suggestions.*

 

Thank you 👍

 

Thanx

When the very vague P0700 code popped up I was thinkin' "piggy back" so I erased the codes and rescanned. It was P0700 first and as soon as I started doing things with the truck (revved engine or dropped it into D or R), the other codes joined in. Some only after driving for 20+ minutes away. The P0700 was always the first code - for months. Even the trans mission guy I know told me there are just too many "O Rings," seals, gaskets and other things in the modern transmissions now. In the 60s. 70s and 80 most Automatics could be rebuilt by changing out the bands and the oil or repaired by rep[lacing a modulator or other easy to reach piece. No so any more. He says ; since it has to come out anyway, why work around old parts? Just do it all.

I am gonna watch this thread for a little longer for other ideas (while I save up for the rebuild I may have to do)

 

Couple questions:

Mileage?
Did you do the rebuild yourself?
What is your expertise?
What troubleshooting has been made?

Depending on the model if it has the remote oil cooler some models need the lines being purged else you end up with foamy oil, no pressure in some parts of the transmission and eventually all kind of bugs. Oil level will be affected as well.

That is what comes to mind right away.

As for rebuild things. From personal experience. All defects have a reason. On worn stuff fixing one defect may "uncover" another. A broken check valve may be the reason for a clutch not to shift but the heat it produced in the hydraulic system may have eaten away an o-ring downstream and now revers is no longer working. The big issue with rebuilds is:

- Do you have the correct manuals?
- Do you have the expertise?
- Do you have enough knowledge to be able do discern/find the first problem and ensuing problems?

Addition to the above (hard earned personal experience)
- The hardest part is to distinguish between something needing a single item repair or if you have to completely rebuild.
- When rebuilding old stuff (and I'm doing that for money) most of the time you have to take it apart "completely" and rebuild also "completely".

What I would suggest:

The 4L60E is such a common transmission that you should be able to find the required info on the net.
Try to get a hold on the real service manual and follow the troubleshooting guide.

Start from first to last in troubleshooting:
- Fluid type and level
- Leaking check (or wash down to be able to check after test drive)
- Comprehensive test driving trying all possible shift patterns - possibly with OBDII connected.

Then:
- Shift lever and cable linkage (mechanical)
- Electrical fuses
- Electrical connectors from the ECU (not sure if the 98 still has a separate PCM)
- Electrical connectors on the harness to the tranny
- Most important (including checking the single pins for corrosion and correct seating) the connector to the tranny
- If you have the manual electrical diagnosis voltages and resistance on the various check points.
- OBDII codes?
- Extend to the transfer case for proper functioning

Have I missed something? Anybody else?