no forward gears on my 4L60e, what up...
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.
Last edited by old yukon; 12-18-2010 at 12:32 PM.