2-3 shift slip, 4l60e, does Corvette servo help?

[PeteyG708]

If you are slipping in 2nd to 3rd, watch out because that is an indicator that the trans is on it’s way out. My 4L60E started doing that and shortly after, I lost 4th/OD altogether, and then 3rd. Needed a full rebuild.

 

[thewedge]

I have a 96' c1500 ext. cab. I had the same problem as you. Its not long before the tranny gets worse. I also thought about the 4l80 swap, but along with the computer pin adjustment and the driveshaft rework it became a real headache. From everything I had read and all the videos i had watched on Youtube it looked like I could get my old 4l60e rebuilt if i could just find the right guy. It took me about 4 months and lots of searching in my area and areas that were within 100 mi. but I finally landed a guy that use to work for a tranny shop and was doing it in his garage. I asked for a tranny that would pull 5000 lbs. on a trailer and last a good long while. He said he could do it. So he rebuilt the 4l60e with all the HD parts including the corvette servo a shift kit and a new torque converter. It took him about two weeks to do because he has a day job too. I've had it for around 6 months and couldn't be happier. I run it pretty hard and it has passed all the tests. So... just keep looking for the right guy. Their out there! Oh I for got to tell you how much it cost. $1200.00 and there was no tax!

 

[PeteyG708]

Nice! Mine was $1650, but that is the mark of a good trans shop... no fuss no muss, and gets it done right!

 

[olskool]

I am new here, I am a professional transmission man for the last 40+ years. a servo will not help an actual slip. I here some of you on here say a 4l60E is not worth rebuilding, wrong! its, who is building it. they were designed to work and when put together correctly they will do just that. and by the way Lube Gard dose nothing to stop or prevent slipping. the best thing you can do for your transmission is bypass the radiator and run a large cooler. if you run the fluid through the radiator and cooler it will restrict the flow use the cooler only,,,,,,,

 

[chipskittles]

Professional Transmission man, I was good with what you said except the part about bypass the radiator cooling. I am no expert on thermodynamics but everything I have ever read from people who knew what they were talking about says that liquid cooling(radiator cooler) is a much much much more effective cooler than a purely air cooled radiator. For that reason, you are supposed to keep the in-radiator transmission cooler. The radiator cooler will maintain the transmission fluid temperature at engine coolant temperature, for better or worse. The external(air) cooler comes into play because it will drop the temperature lower than engine temp. Again, I am not a thermodynamics engineer, but if this weren't true, then why liquid cooling at all? Think how much the auto makers would save by building air cooled engines with an air cooled cooler for transmission. I run an external transmission cooler at the recommendation of my transmission shop too, but I plumb it through the radiator first. It just makes sense.

 

[olskool]

well have you ever seen the inside of a factory cooler? they are about the size of a toilet paper to paper towel roll. they really are not much. they restrict the fluid flow from the external cooler you put on, and if you rebuild a unit then run the new fluid through a funky curded up cooler that is most likely half stopped up you are defeating your purpose. and by the way you will never flush out all the metal with cooler flush, but the psi your transmission pump puts out it will, right back into your unit! people rebuild them and then say they are junk when they have a problem, I wonder why?

and back in the day GM did have air cooled transmissions in vegas that worked just fine,,,,,,,,,

 

[chipskittles]

Sure I have olskool. I'm not disputing that radiators get gross inside. I also don't dispute the flow issue. I didn't mention it. I was simply pointing out that liquid cooling is far more effective than air cooling. I do believe that you are a professional transmission man, and probably a good one. The thing about specialists is they know their stuff, about a specific thing. Vegas? Grew up with them, they were not well thought of vehicles back in the day. Something about rusting bodies and aluminum engines. I guess the transmissions were good, I believe you.

 

[olskool]

yea the transmissions in the Vegas were 250 thm they were almost the same as a 350 but instead of intermediate clutches they used a band for second gear with a servo in the VB to apply it. they had the 250s in a lot of other vehicles that were fluid cooled also. the ones in the Vegas that were air cooled had large holes in the bell housing for air to flow through. you could interchange the fluid cooled ones for 350s and vise versa. in appearance they looked like a 350 except they had the band adjustment on the side of the case, a 350 had none.

 

[chipskittles]

That is good stuff to know about the 250, I don't know much about GM transmissions outside of the TH350, 400 and their electric versions. Never made sense to me why GM couldn't get along and have fewer transmissions. So now you have entire factions that worship the 2004r and the 400. Just about everyone hates the 700r4 universally anyway lol

 

[redfishsc]

Just wait until government regulations force these automakers to install in these trucks a CVT transmission made from recycled hemp and vitamin water bottles