Transmission failure '01 Yukon

[100R1]

I can not beleave it. No warning, No signs of failure!

 

driving to in to work and only 1/2 block away, pull away from red light normal acceleration and it acts like I just put it in neutral. Down shift lever to 3, 3 Etc and nothing, Nadda.

 

Coast into work pull a fred flinstone to back in parking stall and check everything, Goes into park, goes into park. but still nothing in reverse or forward. So I rule out the linkage.

 

Go out 1/2 hour later and works ok in forward, statr to back up in reverse and moves a few feet and Nadda. nothing.

 

Ok call AAA and tow me to the Dealer, First time to the dealer service and pulls up everthing on record still under 36/36, plus since they will keep it overnite I get a paid for rentall

 

I still don't know what is wrong with the Yukon, but hope to hear soon

 

Now here is the starnge part, I called a chevy dealer which is only 3 blocks away and to bring it in and the service writer told me that since it was still under the 36/36 factory warr. I HAD to take it to a GMC dealership for service, That sounds weird. I use to work at a buick dealership (20 years ago) and it never mattered as long as it was a GM vehicle and we had the expertise to do the repair.

 

I am starting to think I better buy a extended warr. to cover myself after the 36/36 expires.

[asepgrad98]

I HAD to take it to a GMC dealership for service

 

i call BS

[03z71]

I HAD to take it to a GMC dealership for service,

This is a new policy that I have heard of several dealers inforcing now. Apparently GMC dealerships were getting upset that people with GMCs kept taking them to Chevy dealers for repairs so they decided that for warranty repairs you have to go to the GMC dealership if you have a GMC. I'm not sure how strict of a policy this is, but from what I have heard, it sounds like there's no way around it.

[03GMCinBC]

Just curious, how many miles did you have on that tranny? I dropped out before 36K? Wow...

 

I always keep mine under warrant throughout the loan, just because of this.... that is an expensive repair.

[Mule]

I  HAD to take it to a GMC dealership for service,

This is a new policy that I have heard of several dealers inforcing now. Apparently GMC dealerships were getting upset that people with GMCs kept taking them to Chevy dealers for repairs so they decided that for warranty repairs you have to go to the GMC dealership if you have a GMC. I'm not sure how strict of a policy this is, but from what I have heard, it sounds like there's no way around it.

I had this happen to me in Anchorage, but was treated so poorly by the GMC dealer, that I returned to the Chevy dealer and explained to the manager that I would prefer to bring my warranty AND non-warrenty work to her instead of the other dealer. They fixed it, and I went back to them ever since.

[03z71]

So what gears did you end up losing? I had my transmission (same transmission) die in my '00 Jimmy at 38,000 miles. I lost reverse, 2nd, and 4th. When I had it repaired, I found out that the sun gear was stripped. Apparently this is not terribly uncommon (considering how many vehicles use the transmission though, I guess the number of failures is low). In looking at it, the sun gear is obviously the weakest part of the transmission.

[100R1]

dealer called before they closed and said they have started a inspection and so far have found that the "reaction sun shield" has expanded and the reason why when warmed up would not move (in any gear)

 

The reaction sun shield is related to the sun gear and seems to be one of the weak links in the 4L60E tranny. 03z71 you seem to have had a similar problem in the past.

 

Seems I saw a TSB on this somewhere in the past.

 

I only have 31,343 miles on the Yukon

 

Anyone know what causes the Reaction sun shield to fail?

 

 

 

I'm driving a loaner from the dealer, '04 GMC envoy....I cant wait to get the Yukon Back! It's going to take them until monday to get fixed.

[03z71]

My problem was also the reaction sun shield. This is definitely the weakest link of the 4L60E (and I can unfortunately base this on experience!). Here is what they look like:

 

 

In my case, it didn't expand. The teeth were stripped. Here is a closeup of mine showing the stripped teeth:

 

 

As far as what causes it to fail, when you look at one, it's easy to see: they don't look very "tough" compared to the rest of the transmission. I think the percentage of failures is small, but since there are so many of these trannys in use (it's found in almost all rear-wheel drive GMs with the exception of 3/4 ton and up trucks), the overall number is not small.

[Texas Z]

Mine went out at around 20k. I lost overdrive and reverse. Took it to dealer and they said it was the reaction sun shield and that he sees alot of them go out. That kinda scared me.

 

Has anyone had their reaction sun shield fail more than once in the same vehicle?

 

When the dealer replaces it, do they replace it with the same part or use a better quality part?

 

I am worried that since mine failed with only 20k, it will fail again at 40k if the same part is used.

 

Thanks

[03z71]

Texas Z,

 

I asked the dealer that same question when my tranny went out. They said they have never (knock on wood) seen a vehicle come back after having the sun shield replaced and the tranny rebuilt. I asked if the same part was used and they told me that it was the same part though. So take that for what it's worth. In my searches on the internet when my tranny died, I couldn't find anyone with a rebuilt tranny with problems with the sun shield.

[100R1]

No new news about my Yukon, But that was expected as the service writer said it would be monday before they really would be able to fully do a tear down.

 

03z71,

Thanks for the pictures, The pictures of the reaction sun shield is what I was thinking it was when the service writer told me what the problem is. I think they will find just like your pictures mine is also stripped out as this seems a common problem.

 

How much of a re-build they do on your tranny besides the sun gear and reaction sun shield?

 

Do you still have the '00 jimmy ? if so how many miles do you now have on it?

 

 

I know I saw a TSB on this but I can't find the link I had to alldata that allowed me to view it or perhaps the info came from the GM tech website that I had some access to for a short time period.

 

(I found a reference to a TSB 00-07-30-022 for the reaction sun shell, But I cant find access the TSB)

 

It also seems that I saw something some place that GM has improved the parts and that the 4L60E after a certain build date has the newer parts in them, and that any re-builds would have the improved parts installed.......

 

 

I was also suprised that the dealership will re-build my 4L60E instead of installing a "ready Re-built" transmission from the parts bin.

 

Now I'm concerned that it will happen again or that the rebuild will not be 100% correct. I will be using this Yukon for towing my travel trailer and I would hate for the same thing to happen while towing up a 8% mountain grade !

[Markeaux]

Dayum that sucks ... and it sure seems like a lot of failed tranny's from a small cross-section of posters to a specific forum ... not making me feel too good about mine, especially after boosting the shift firmness and reducing the shift timing on my 4L60E (but actually that may help make it live longer )

[NothinButBowTies]

I would like to have around 400 horses out my Sierra, by the time I am done playing. From what I have read at LS1Tech, I will be a prime canidate for a trans rebuild. Those guys over there comment that the 4L60E is the weekest link in our trucks. For them to be able to hanlde 400 - 450 horse motor, it takes about 1000 bucks in parts and 500 in labor.

Sorry to hear that happened. Just be glad that you didnt buy a Dodge...they make the worst auto trans out of the big three!

[100R1]

I would like to have around 400 horses out my Sierra, by the time I am done playing. From what I have read at LS1Tech, I will be a prime canidate for a trans rebuild. Those guys over there comment that the 4L60E is the weekest link in our trucks. For them to be able to hanlde 400 - 450 horse motor, it takes about 1000 bucks in parts and 500 in labor.

Sorry to hear that happened. Just be glad that you didnt buy a Dodge...they make the worst auto trans out of the big three!

Here is a very interesting site that builds performance transmissions they have 2 versions of the 4L60E up to 450 HP and over 450 HP. Price seems very cheap for a rebuild with a 1 year warr.

 

If I was not under warr. I would consider something like this especially since they "BEEF" up the weak parts. One of them is the "BEAST" reaction sun shell

 

 

Here is a linkPerformance transmissions

 

Hell If I could I would go and buy upgraded parts (like the BEAST) out of my pocket and give them to the service tech to rebuild under My GM 36/36 warr. But I know That they won't do it.

[03z71]

How much of a re-build they do on your tranny besides the sun gear and reaction sun shield?

 

Do you still have the '00 jimmy ? if so how many miles do you now have on it?

I believe they just replaced the sun gear and reaction sun shield, cleaned it, replaced the filter, put it back together, and filled it with fluid. I now have almost 66,000 miles on it (28,000 miles on the rebuit tranny) and it's been fine ever since.