Trans Question

[ChriSS K]

I know these things can be hit or miss, but what is the average life of a trans that doesn't get beat, no tune, daily driver, no racing and no towing? Just your basic everyday use with the occasional 4X4 in the snow. Also what is you opinion on replacing fluid and when do you feel it should be done? I know its one of the weakest links on these trucks so I just wanted to see what other people are doing/getting out of them. This is on a 5.3L. Thanks

 

[RedEnvoyDenali]

I know these things can be hit or miss, but what is the average life of a trans that doesn't get beat, no tune, daily driver, no racing and no towing? Just your basic everyday use with the occasional 4X4 in the snow. Also what is you opinion on replacing fluid and when do you feel it should be done? I know its one of the weakest links on these trucks so I just wanted to see what other people are doing/getting out of them. This is on a 5.3L. Thanks

You will get lots of opinion on this, so here is mine.

First and foremost change fluid and filter regularly.

I am a firm believer in a tranny cooler on any truck whether it tows or not. See the attached chart. Heat kills transmissions and you can over heat them a lot of different ways, the simplest is just getting stuck in the snow. I believe the biggest one you can install will work and I like Tru-Cool since they have a bypass when the tranny fluid is cold.

Transmission temperature/failure chart.

With a tranny cooler I had a 76 GMC Van with 350 turbomatic tranny that had over 500,000 miles. It was a little loose but we drove it to the junk yard.

Good luck with whatever you do.

 

[jbones]

Regularly sounds subjective for sure!

The "08" Envoy owner’s manual suggests of 100,000 miles. Just throwing it out there as my driving habits match the OP, and trans feels good in my “08” TB, so I figured I'd go with the 100,000 since I don't meet any of the footnote conditions. Is this bad thinking?

Foot note:
(h) Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
− In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
− In hilly or mountainous terrain.
− When doing frequent trailer towing.
− Uses such as found in taxi, police, or delivery
service.

?

 

[ChriSS K]

Regularly sounds subjective for sure!

The "08" Envoy owner’s manual suggests of 100,000 miles. Just throwing it out there as my driving habits match the OP, and trans feels good in my “08” TB, so I figured I'd go with the 100,000 since I don't meet any of the footnote conditions. Is this bad thinking?

Foot note:
(h) Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
− In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
− In hilly or mountainous terrain.
− When doing frequent trailer towing.
− Uses such as found in taxi, police, or delivery
service.

?

The thing with your set up vs mine is I'm not sure what trans your have with your 4.2? If its different than mine then I guess its all relative? I know the 4L60E is a weak trans and yes heat will kill any trans, but I don't have enough experience with this trans in this set up. I'm use to my 95 caprice....

 

[jbones]

"4L60E" sounds about right for mine.

 

[RedEnvoyDenali]

The thing with your set up vs mine is I'm not sure what trans your have with your 4.2? If its different than mine then I guess its all relative? I know the 4L60E is a weak trans and yes heat will kill any trans, but I don't have enough experience with this trans in this set up. I'm use to my 95 caprice....

Although they are different they are still automatic transmissions. Expensive to fix and frustrating to deal with when they don't work.

I believe that most manuals say to do the fluid and filter every 50,000 miles. Considering the cost of this service and the price of a rebuilt/new tranny I will do this every other year regardless of mileage. Remember if you just change the fluid in pan you are not even changing 1/2 the fluid. The total change is around 13-14 quarts while the pan will hold only about 5 quarts. (Of note when you do the first one it is a good idea to put in a drain plug to make the next one easier). Costs very but I would suggest around 50.00 will get you an partial change and a filter.

That is why I recommend a tranny cooler for any vehicle, no matter whether you tow or not. Terrain, and traffic conditions can happen to anyone, anytime. I am not sure if the 4L60E is a weak tranny or not, I do know there are MILLIONS of them out there so on that basis there will be failures. After that there is no accounting for people and the abuse that they inflict on them.

There are various things you can do to the tranny to prolong its life. A PCMforLess tune will help with the shifting, so will an accumulator upgrade, on top of these the basics preventive maintenance if probably the first line of defense.

I don't know if the instructions for doing a full fluid change have migrated to this new site but they are on the OS so they are available if you need them.

You will also hear a lot of discussion about flushing vrs changing. I prefer to change the fluid (at least in the pan) and the filter. A flush leaves a dirty filter, dirty magnetic in the bottom of the pan.

 

[jbones]

I believe that most manuals say to do the fluid and filter every 50,000 miles.

I guess the "08 Envoy and TB manual is not in the most manual category, as they clearly say 100,000

 

[RayVoy]

The thing with your set up vs mine is I'm not sure what trans your have with your 4.2? .

"4L60E" sounds about right for mine.

Although they are different they are still automatic transmissions.

Until the 6 speed became available, the 4L60E was the GM "bread and butter" transmission, it was used in ALL GM medium duty applications (rear wheel drive, the 4T60E is for front drive).

I am quite sure, the 4.2 and the 5.3 both use the 4L60E tranny, while the ss trucks use the 4L65E.

 

[djthumper]

Regularly sounds subjective for sure!

The "08" Envoy owner’s manual suggests of 100,000 miles. Just throwing it out there as my driving habits match the OP, and trans feels good in my “08” TB, so I figured I'd go with the 100,000 since I don't meet any of the footnote conditions. Is this bad thinking?

Foot note:
(h) Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
− In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
− In hilly or mountainous terrain.
− When doing frequent trailer towing.
− Uses such as found in taxi, police, or delivery
service.

?

I guess I get the alternative mileage since I fall into 4 out of the 5

The thing with your set up vs mine is I'm not sure what trans your have with your 4.2? If its different than mine then I guess its all relative? I know the 4L60E is a weak trans and yes heat will kill any trans, but I don't have enough experience with this trans in this set up. I'm use to my 95 caprice....

Until the 6 speed became available, the 4L60E was the GM "bread and butter" transmission, it was used in ALL GM medium duty applications (rear wheel drive, the 4T60E is for front drive).

I am quite sure, the 4.2 and the 5.3 both use the 4L60E tranny, while the ss trucks use the 4L65E.

that sounds correct to me.

 

[ChriSS K]

What is the current cost to get the trans replaced? Is it better to get a reman or if you know a good rebuilder to just have him do it? I like the tune idea, but worry about warranty issues. If you load the tune yourself and put the factory tune back in they can still see that you did that correct?