[old yukon]

I need some advice on my 4L60e in my 200 5.3L 4WD Yukon.

A few months ago I began to feel noticeable slipping in my tranny. them got P1870 DTC (Transmission Component Slippage) . I cleared the code and it didn't return. The slipping became more noticeable especially on hills and high car park ramps.

A month later I began having a problem with my tow/Haul coming on and getting stuck in tow/haul by itself and i could switch it off, the off by itself, then on. I dropped the pan and replaced the AT fluid and filter, no real issues there, the fluid was a bit burnt from the previous power flush a year ago, and I was first time the flitter had every been replaced(see image).

All was ok, but still had slipping especially in 3rd to 4th. I kind of felt like I had no 4th gear and 3rd would just climb up to 120+ km without any gear change. funny enough i could not rev part 2200 rpms when a few months ago, 4-5,000 rpms was not an issue. except in tow haul the rpms was not a problem.

Then things got worse, still with the tow/haul issue, I pulled into a car park and lost reserves when trying to straightening up the Yukon.
I left it on a angle, and came back after half an hour and the reverse was working again. drove down the ramp and over the first speed hump, and the then the second, hay, no gears, no forward gears to get my Yukon over the 5 cm high speed hump, I was revving and going nowhere. Tried the manual gears nothing, just enough in 1st with a bit or revving to get it over the hump.

Out of the parking lot I pulled it to the side of the road, and turned it off, in hope the gears would come back somehow, like the reverse did. Not quiet that fortunate. I had half a gear to get me rolling down the road and onto the highway not planning to stop the Yukon until i got home (3km away).

When home i check the fluid which was a trad low, so topped it up, no change when driving around the block. I would rev and go nowhere fast like when the chain falls of the pushbike when I was a kid !
The fluid was clean and no burnt smell. No codes came up at all. and i cant figure it out. All I have left is half a first gear and a reverse, nada for the other gears.
Hope its an easy fix. I don't want to rebuild my 4L60e if I can avoid it.
Haven't gone under yet, will be doing so in about a week.

[Crosley]

if this is the 243k miles trans you mention in another thread,

Its about the 4L60e tranny in my 2000 5.3L yukon (243,432 miles on it and just went for the first time

The trans is done, finished, kaput. 243k miles is 2.5 times the average useful life of the 4L60e trans.

Pull it out and have it rebuilt properly. There is no magic elexcer that will fix it. there is no magic adjustment

[old yukon]

Thanks Crosley for the no sugar coated bitter pill, you have saved me a big headache i bet.

Short and to the point is the way i give advice also, not waisting anyones time.

Just for curiosity what do you think is gone on it, (i know how long is a piece of string..) buy generally speaking what does it sound like ?

Yep it is the same 200+k mile one.

Old Yukon

[SSedan64]

Sounds like everything other than the Low/Reverse clutches are completely burnt up, 3-4 clutches, 2-4 Band etc..
Like Crosely said, it's gone & will need a complete overhaul.

[Crosley]

Originally Posted by old yukon

Thanks Crosley for the no sugar coated bitter pill, you have saved me a big headache i bet.

Short and to the point is the way i give advice also, not waisting anyones time.

Just for curiosity what do you think is gone on it, (i know how long is a piece of string..) buy generally speaking what does it sound like ?

Yep it is the same 200+k mile one.

Old Yukon

You ask questions, I answer the best I can.

I did not save you anything. You need a trans rebuilt and it ain't cheap for parts and labor. Mistakes are expensive


some more straight talk:

i;ve done this work for decades. I've answered tech questions on line for 12 - 14 yrs.

I've heard many of the same questions from vehicle owners in person and online:

Why was the trans fine yesterday?
Why did the trans just quit at the stop lite?
Why would this happen after only 243k miles?
Why does it only back up?
Why does it only change gears once then quit?
Why ..... yada yada yada yada?
Why can't anyone tell me the simple answer?
Why did it only slip once then quit?

Drop the pan again, put more filters on it... add some brake fluid, add some Seafoam , add some Lucas stuff.... if you like.

If you R&R the unit yourself, be careful.

Chances are you will break the neutral safety switch trying to unplug connectors

I gave you my opinion and always remember my opinion is worth what you paid for it.

[old yukon]

Thanks for the reply guys.

Ive thrown in the towl on the 4l60e rebuild challange, thats one part of my yukon i dont want to take on ;(

Is the Tow/haul issue part of the dame problem ??

4L60e R.I.P.

Old Yukon

[kc8oye]

the only trans failure I've never been able to explain was when my 440-t4 died.

the car was driving great.. no slipage. no signs at all anything was wrong..
parked it at the grocery store.. came back out.. nothing.. no drive, no reverse..
if I reved the engine to red line in drive, I could just get the car to crawl about 1 or 2 mph.

the shop never did tell me what failed.