More 4L60e issues

I have a call into my buddy about it, but he's not in the shop yet. He rebuilt the tranny. He's a stand up guy, and I'm sure he'll make it right......but until I hear back, I'm curious what is going on.

Had the transmission rebuilt.

Seems to function fine, with the exception of 2nd gear. Seems to be slipping with any sort of aggressive throttle in that gear only. Example. Van is at a stop sign and I need to turn and go up a hill. First gear is fine as I accelerate, goes into second, and seems like it is almost in neutral, rpms sore, then I let off the gas, and it seems to recover I ease on the gas and we seem to accelerate, get to third and everything is back to normal. Fluid level measures normal on the dipstick. I don't know that the fluid smells burnt, but it does leave a blackish residue on the cloth I use to clean the dipstick. Less than a 1000 miles on the rebuild.

I'm suppose to tow to a race on Friday. I'm guessing I better come up with other arrangements at this point, unless you all think this might be an easy fix.

Just strikes me as odd that it's a second gear only issue.

I did a a little googling and if OD is fine, sounds like a 2-4 servo problem, either a bad o-ring or bore. I would have broke out a manual, but I don't have one.

I'm finding that too. Transmissions are like magic to me....no clue how they really work. Is the servo something you can get at with the tranny in place?

Could I have harmed it in this state?

Yes, trans can stay in vehicle.

I can't definitively say no, but more like highly unlikely. Given that servo also works in OD/4th on the 2-4 band and OD is OK.....

Thank you Ranger50.

So by my logic. Inspect/change the servo. Fluid likely has to be drained and replaced.

sachilles wrote: Thank you Ranger50. So by my logic. Inspect/change the servo. Fluid likely has to be drained and replaced.

No the 2-4 servo is that big ugly looking round thing on the pass side of the transmission by the dip stick.. It can be changed and instpected with out taking the pan off the transmission and draining the fluid...

....and thank you crazy canadian. See I know nothing.

I'm looking on rockauto to find the part cost, and I see nothing listed as servo. What is the officially official name for the servo?

I can buy the corvette 2/4 servo "set" for about 15 bux. FYI.

Gracias!

Any time that its slipping, its potentially doing massive damage. Avoid driving it, but if you have to, be super easy on 2nd gear. Trick it into shifting.

As long as its slipping, its like running a manual tranny clutch half-engaged. Massive friction and wear.

If the servo doesn't fix it, pull the pan and valve body. Its likely your separator plate has one of the check balls stuck in it, or at least one of the holes is wallowed out. There are grommet kits to fix it, but its only like $20 to order a new one from the dealer. (and that is a better way to make sure you get the right one instead of buying a kit with 8 different plates and try to match them up.)

Curtis, no intention of driving it. I can AAA it to the shop, if needed. It's not a daily driver.

My first question is, does reverse work?

And if the answer is yes, return to your regularly scheduled suggestions already posted.

If the answer is no, sadness!

Reverse does work. Dropped it off at my buddies shop. I'm not convinced 4th wasn't slipping, but it could be paranoia at this point. Curious to find out what the issue is so I can better understand the black magic that makes autos tick.

Well that's good news. Id hope for a band servo issue since it correlates to 2nd and 4th slip issues and just happens to be about the only cheap/easy thing to fix. Assuming the band itself isnt ground down to metal and hasnt turned the drum black and blue.

4th gear slips arent always obvious since most of your high-load acceleration is done by the time you get into 4th. Even harder to notice if you dont have a tach and arent already suspicious.

Can the Van's ecu cause an issue?

Buddy suspects the ecu, and I don't think it would be an issue. I did replace the ecu in june of 2012, as being suspect of a stumble. Got a reprogrammed one from ebay. New ecu did not cure anything, turned out to be the non ac-delco cap/rotor. So the old computer is still sitting in the van as a spare.

He claims it slips in all the gears, including third. So he doesn't think it's the servo.

Ecu seems like a wild goose chase.

If your friend thinks the ECU is causing his transmission to slip, i would doubt his ability to correctly identify a transmission slip in the first place. I think someone who knows what a slip is should double check him on that at this point..

Yup, coming to that conclusion myself. However he wants to rule it out before pulling the trans. At that awkward point where dealing with a friend is going to suck.

Would you believe I'm still dealing with this?

He wanted to rule out the ecu, so we had to wait for joe schmo to reprogram the computer. That appointment was June 28.

if that was a magical fix, one would think he'd be calling me to say all is well come get your ugly van out of my lot. Instead I've called a couple of times only to get passive aggressive responses on facebook about being busy not directly to me. His shop is an hour away. I fear this is going to end poorly. Hoping he'll return todays phone call, else I'll have to go visit in person.

I'm really an easy going guy, I'm a push over(duh!). A simple call of I didn't get to it would likely suffice so long as some sort of battle plan is discussed.

sachilles wrote: A simple call of I didn't get to it would likely suffice so long as some sort of battle plan is discussed.

have you told him that?

AngryCorvair wrote:

sachilles wrote: A simple call of I didn't get to it would likely suffice so long as some sort of battle plan is discussed.

have you told *him* that?

I've told his voicemail this.

As of an hour or so, I also told his wife this who answered the shop phone, where I was told he'd call me back in a couple of hours as he was going to get the van today. Not sure where it was that it needs to be retrieved, as he'd reported to me last wednesday that he'd retrieved it from whomever had to deal with the ecu.

I've communicated it by message on facebook as well.

If I don't get a call back today, I'll take time off from work and communicate it to him at the shop.

There was a TSB from GM and a kit to update the harness to fix flaring between shifts, but your description sounds more serious than just flare.

It applied to my 96 s10, but I'm not sure what other years and models. I'd have to google to try to find the number for the TSB again.

It was to correct a potential ground issue between boards in the ECU. If it is a ground issue reprogramming the ECU won't help.

Yup, seen it. You basically put a jumper wire in on from one pin on the ecu to another ground pin. That had been done at some point in the vans life, and you can see it on the ecu connector. Noticed the jumper long before any of this tranny stuff when I bought it.