4t60e swap

[Schmieder]

I dumped 2 and a half gallons of fluid in, trust me it is full. I will check the vacuum modulator out tomorrow. I had this same problem with a transmission about a month ago. It also was the later style 4t60e, i changed it as well thinking I had a bad transmission. But I am looking at wire prints ( Haynes Manual) and this later style 4t60e is a little different inside, compared to the earlier one.

I'm on the third transmission now, the previous three were all used and swapped out at no cost to me, but my labor. It's been pretty frustrating. My labor will pay off soon, I hope.

Has anyone else ever put a 4t60E from a 97 into a 93 lumina?

Over filling the fluid will cause foaming and that foam will not compress like straight fluid causing really bad slip, long shifts, etc. The 4t60e, and many other autos, need a very precise amount of ATF. Too much fluid can cause all sorts of havoc just as well as a lack of fluid. Because the air pockets compress and that means the shifts will take far too long and the trans will slip like crazy.

Does your ATF smell burnt or have a brownish color when wiping the dipstick with a clean towel?

Not saying you don't know what you are doing, just trying to help out. I would get the engine to operating temp and drive it a bit and see what your ATF dip stick looks like. A quart too high and you could be foaming the fluid.

[robertisaar]

some of us run a quart over in our 60Es to keep the pump from cavitating during high speed cornering....

above 1 quart over could be a problem though.

[Schmieder]

some of us run a quart over in our 60Es to keep the pump from cavitating during high speed cornering....

above 1 quart over could be a problem though.

Thats what I was thinking. Just dumping in 2.5 gallons could easily put it over the limit. I never had foaming issues with an over fill but I have heard about it often enough.

From what I found, the ATF fluid capacity varies from 6.0 qts for 95 and earlier, 7.0 qts for 96-2001 and 7.4 qts for 2002+ (as per Haynes Manual)

1 gallon = 4 qts.
2.5 gallons = 10 qts of ATF.

You are WAY over filled if you really put in 2.5 gallons. By as little as 2.6 quarts and as high as 4 qts.

You are foaming up the ATF fluid, I am 99% sure now.

Drain as much as you can, measure how much you drained and subtract that from 10 qts. Refill to achieve 7 qts of ATF and then check the levels from there.



I don't know if you need to drain ALL the fluid if it was foamed up or not. It may have ruined the ATF. Maybe Robertisaar knows, I would dump it all and refill to the dipstick level. Then warm it up and fill as needed while engine is running.

The 4t60e is a picky little b*tch, imho.

[robertisaar]

just because the fluid foamed doesn't mean it needs changed.... eventually, all the little air bubbles will pop and the fluid will be exactly as it was before the foaming, assuming it didn't pick up any clutch material or anything like that.

and i thought those numbers seemed wrong....

95 MC 3100:

7.4 quart pan capacity
10 quart complete overhaul capacity.

[Schmieder]

just because the fluid foamed doesn't mean it needs changed.... eventually, all the little air bubbles will pop and the fluid will be exactly as it was before the foaming, assuming it didn't pick up any clutch material or anything like that.

and i thought those numbers seemed wrong....

95 MC 3100:

7.4 quart pan capacity
10 quart complete overhaul capacity.

Just as long as the fluid didn't get burned, I agree it can be reused.

I was just quoting Haynes for the ATF capacities. It was stated as a fluid and filter change, so it may not have meant FULL capacity.

If 10 quarts is the complete overhaul capacity then I stand corrected.

But there isn't much I can see external to the trans that would cause terrible slip besides improper fluid levels and/or excessive vacuum or badly tuned adjustable vac modulator. Going through 3 4t60e's and still having trouble would indicate an external problem to me. But thats hard to say w/o hands on help. Since the 4t60e line pressure is vac controlled, I don't believe ANY pcm issue would cause bad slip. Shifting problems yeah, but excessive slip, not the PCM.

When you find the problem please post it up as I am deeply curious now.

[rcp4207]

Today I swapped the transmission lever position switch out. I also swapped the vacuum modulator out. Drove the car around for about 15 minutes, still hesitates on initial acceleration. Also stalls out when coming to stops. When it is in first gear or second gear, acceleration is great. But drive and overdrive suck. I got back home and left it running on a level surface, fluid level is right above the bottom hole on dipstick, I don’t think a pint of fluid is going to change anything. The fluid is still clean, and it does not smell burnt. I had this same problem with a previous transmission. I thought it was a bad transmission, and changed it again. I am convinced that the wiring for a 97 Lumina’s transmission is different than the wiring for a 93 Lumina. I looked at the various wire diagrams on this site, some are pretty helpful. I have a Hayne’s manual as well. But for all the different applications that these transmissions are used, I think I am going to just pull the transmission again. Unless anyone has any good suggestions. I have a U-pull-it type yard that has a very good selection of donors. They said as long as I bring it back within 45 days, I am good to go. What other type transmissions, besides the 4T60E, would work in a 93 Lumina ( VIN T)? Could I put something else in to get better performance? Or just stick with the 4T60E? I will make sure it is from the same generation this time.

[robertisaar]

when you throw the shifter into 1st or 2nd, you bump up line pressure considerably, which is why you're not experiencing slip at those points.

the 93 lumina would have the earliest style of 4T60E, the only direct swaps would be the 91-93 3.4 LQ1 and the 93-94 LH0 4T60Es. those should drop in without any changes necessary. the LQ1 version will have a slightly shorter FDR though, 3.43 compared to 3.33.

there's nothing electrical that will cause this unless you're not actually starting off in 1st gear(meaning the trans is in fail-safe mode and defaulting to 3rd gear when the shifter is in 3 or 4, and in 2nd gear when the shifter is in 1 or 2.

[rcp4207]

If it was in failsafe mode, how do you get it out? Would it be the shift linkage out of adjustment?

[robertisaar]

normally, failsafe mode will reset and be cleared every time you key-off.

failsafe is caused by the PCM not allowing the shift solenoids to be grounded(PCM grounds them to enable them), or if the solenoids don't have a good +12V from their fuse(which is the TCC fuse in the underhood electrical center #1). oddly enough, the TCC is powered by the indicator fuse in the interior fuse block.

now, when both shift solenoids are off, the trans will be in 3rd gear, but the shifter can cause a manual 3-2 downshift due to the way the valvebody is setup. from the sounds of it, line pressure bumps up when you have the shifter in 2 and 1, so the linkage sounds like it is fine, though is it possible that you're actually just causing the trans to start in 2nd instead of starting out in 3rd?

[rcp4207]

I'll check the fuse next, and for power. I just noticed my right rear hubcap is melted, possibly a brake or bearing issue, hopefully it is related somehow. But is the internal wiring on a '97 4T60E the same as a '93 4T60E? I've had this exact issue with a different '97 4T60E. And what about the harnesses going to the shift lever switch where the linkage hooks up, the '97 had a lot more wires than the '93?

[robertisaar]

the internal wiring is close enough(as long as the shift solenoids and TCC circuits are matched), i ran a 95 4T60E(has same setup as later ones) on a 93 PCM for a while without this kind of issue. the PCM always thought i had the shifter in positions above 1, so i couldn't force 1st gear above the normal shift speed maps, but never this kind of craziness.

the shift lever switch sounds like where the newer style PRNDL decoder would be. again, wired correctly, it shouldn't be an issue. IIRC, on the 93 and earlier stuff, there is just a p/n and the 1/4 switches.

[rcp4207]

I have finally found what is wrong, please visit http://www.autodiagnosticsandpublish...ansmission.pdf . There you will see that my 93 Lumina’s transmission wiring is different. I plan on doing a re-pin on my connector. Unfortunately now my starter is burned out. I will definitely let you know how it turns out. It might be tomorrow evening before I post anything new.

[robertisaar]

from the sounds of it, i thought you already had the pinouts for the trans connector? otherwise, i would have posted them for you to verify.

[rcp4207]

I did , but I did not see anything I could use like the drawing I found today.

[Schmieder]

I have finally found what is wrong, please visit http://www.autodiagnosticsandpublish...ansmission.pdf . There you will see that my 93 Lumina’s transmission wiring is different. I plan on doing a re-pin on my connector. Unfortunately now my starter is burned out. I will definitely let you know how it turns out. It might be tomorrow evening before I post anything new.

At least the hard part is over with. Now it's just about time and labor.....goodluck man. I hope you get it on the road soon.