2002 Envoy Transmission Problems - GM 4L60E

I just had the Sun Shell (GM 4L60E) in my transmission replaced on my 2002 Envoy with 63,639 miles on the vehicle. The repair shop gave me the faulty part and a letter explaining that the transmission in my vehicle failed because the sun shell spines were stripped. Apparently, this is not uncommon in the automatic transmission repair business. The repair shop explained that this part is known to contain a softer alloy, which is highly prone to stripping. I did not purchase an extended warranty, but feel that GM should be accountable for using parts that are known to fail. Has anyone else encountered this problem? Could you please let me know what you did to resolve and the outcome of your efforts? Thank you.

I have not had the problem, yet, but I was hoping you could share the symptoms that led up to the failure of your transmission’s sun shell. I too have a ’02 with about 66,000.

Thanks.

I did not realize the symptoms until I drove my car today, with the new Sun Shell. Basically, over the last year, my car would take longer than usual to switch gears. Unfortunately, the slipping transmission was not consistent and it had been occurring on and off for the last year. The sound I would hear, I equate to a 'revving-up' type noise. This most typically occurred when I would start my car in the morning. I rarely had this problem after driving around a bit. When the transmission actually failed, I heard strange noises from the engine while driving and while sitting idle. Now, I barely hear the car running at all....quite a difference. I hope this helps.

Thanks for the insight and I am sorry about your problems. I had a ’94 Dodge Intrepid that I traded in on my ’02 Envoy—I put three transmissions in that Dodge and was hoping that the Envoy would not give me the same headaches.

Do you know, or did the people at the repair shop tell you, of a way to tell if the sun shell is going bad besides the revving between shifts you described? I am currently under an extended warranty, but it is about to run out and I am sure my transmission will fail, if it does, one mile out of warranty. Several times, I have felt the transmission slip or the engine race when shifting from first to second gear. Did you experience problems between every gear change? Or was there one shift that was more noticeable now that you have had the problem fixed?

Thanks for your input.

Thanks. I did not discuss that with the shop. However, if you are already noticing the engine "race", I think you should have the dealership look at your trans.
I have never had to replace a transmission in any of my previous vehicles...so I was not sure what to listen for or what to observe.
Thinking back, I experienced the problem sporadically over the course of a year, with some increase in frequency in the last four months. It would always occur when my engine was cold, so I attributed it to not giving the car a moment to warm up. Unfortunately, I did not recognize the problem...until it went out completely. Then, it was really obvious to me that there was a problem. I checked it out after I got home and found that I could not go in reverse and the there were very strange noises come from the engine when it was idling. We had to push the Envoy out of the garage to have it towed. The Sun Shell is supposed to have ridges and the one they took out of my car, was almost completely smooth. I was told that there was nothing I did to cause this problem. They indicated that the GM 4L60E is known to have a softer alloy metal.

I have been driving the car since Monday evening and the car runs great. It certainly is a big difference in how the engine sounds while driving and idling. It is much quieter...much like when the car was brand new. I now have my transmission experience and will always be alert to these problems....
Good luck.

I also have an 02 Envoy with 53,000 kms (I'm in Canada). The gear shift has just died, the car is running but it cannot be moved out of park. We are waiting for road assist to come & pick it up (its still under warranty) and take it to the dealer. I found your msg very interesting since I've also noticed that the truck rev's high (usually in the morning) and goes away after being driven for a while. I have brought this up several times to the dealer & was told that it was normal & that it was just the veh getting "warmed up" and that even warm temperatures (since it was happening in summer as well as winter time) is "cold for a vehicle." It will be very interesting to see what the dealership has to say about this problem.

Interesting. I have just taken my 2002 Envoy LT in the shop for basically the same sounding problem. It runs great, but when first started, usually in the morning, it really winds up before shifting into 2nd gear. All other gears seem fine. The dealership told me it was a clutch fan assembly problem ($800), others told me the transmission needed servicing. So, I had it serviced today, and we'll see what happens. And it doesn't do it all the time - just sometimes. Love my Envoy - hope this solves the problem. Thanks for posting your problems - it gives me an idea of what to look into should this fail.

I have a 2002 Envoy. Today, I was told by the GMC dealer that the transmission is all to pieces and has to be replaced. This is going to cost me $4000. Ever since I bought it, it would rev up in the morning and wouldn't change gears. If you are having this problem and still under warranty, you need to get them to fix it ASAP.

I have a customer with this problem, but its allot worst. The vehicle had no reverse one morning with just little warnings, a load bang that day she said and that was it, but she also wasn't listening for anything she said.
So i have seen this problem at the dealership i worked at as a mechanic but we had one tech that did all the tranny work, so i never got into them but did see it allot.
The sun shell gear teeth strip out and if your careful and dont drive it with no reverse, it should be less money for a rebuild. But some people do and when the metal pieces float around in the tranny it cause more damage, so dont drive it. If you do you will lose 2ND gear next, and it wont have 4Th either.
So as soon as you notice any issue with your truck, stop driving it on the spot, get the tranny overhaul, and make sure you use an aftermarket parts, the dealer parts are to soft of metal and you dont want to chance, try to tell your mechanic that this is common if he dont already know this.
The sad part of this problem is the part only cost $35.00 but $3500.00 later its fixed. The part in all the way in the middle of the tranny, so it has to be completely broken down to be fixed, so it will need a rebuilt kit, the sun gear and shell, and anything else the metal peaces damaged if any. The tranny I'm doing now didn't do any more damage and the lady drove it for days with no reverse, lucky!
So any question's about this problem, hit me up and I will try to help.
Any boat issues, i can help with that too and even will come and do the service if your in the state of Massachusetts.
Good luck

Welcome to AF, but I would suggest you look at the dates on the threads as this is 6 years old and dead, thanks.

The 4l60e is a great tranny! the sun shell usually snaps separating right at the bend leaving the gears intact but separate from the shell. Picture a bunt cake mold and the center hole has gears the bottom at the bend is weaker and snaps. That being said you can buy a rebuilt tranny for 800 or have yours fixed for 500 in parts including a aftermarket sun shell that has been engineered beefing up that bend. Many people get slippage codes and are told needs rebuilding and that is not correct 80% of the time. The TCC valve often wears out and wont hold pressure letting tranny fluid seep by causing slippage and hard shifting. That fix is about $30 and another is TPC solenoid about $40 and then shifting solenoids if you have hard shifts in 1st and 2nd or 3rd the drive and they are $20. My point is be very careful and get 2nd or 3rd diagnosis before handing over your money. Anyone with a little mechanical ability can do most fixes themselves. And believe it or not rebuilding a tranny is not a difficult as it looks. Here is a link to an online step by step class to rebuild a tranny I promise you watch it and you will lose the fear.

https://www.youtube.com/watch?v=SK84Qy_Vu_E&ab_channel=TransmissionBench

Gotta disagree with a rebuilt trans for 800.00, not here in Ny. A little mechanical ability to get into a valve body repair for some of the common codes for hard shifts, that is a bit of an overstatement.

Gotta disagree with a rebuilt trans for 800.00, not here in Ny. A little mechanical ability to get into a valve body repair for some of the common codes for hard shifts, that is a bit of an overstatement.

figure a $1000 with shipping but you can find them close and pick them up to.
$850 plus 150 shipping search it yourself.
And tranny pan 16 bolts and a valve body is 14 bolts if your careful its not hard and the only thing holding 2 switches and valves and solenoids are clips replacing them is not hard either when your match new for old parts. the bolt pattern doesnt allow for installing backwards. If your mechanically inclined most back yard mechanics can do it with no trouble