2000 4WD XLT V10 Automatic 125,000 miles 373 rear end. Only upgrade 285 Cooper STT's. Here's the story: Picking up hay this weekend for the horses. To save some money, we were picking it up in the field. The field is very hilly and we had on about 100 bales of hay (50-60lbs each). Had it in 4x4 Low and had the transmission manually selected to 1st, my son was driving and I was stacking. He was pulling up a hill and the X just stopped. He had his foot all the way down on the gas, but it would not move. Tires did not spin, it was just grunting. He put it in park and we changed places, I had to back down the hill and then get some momentum going before we could get to the top. My question is, is this normal? I would have assumed the tires would have broke loose before it just gave up. We were in a grass/hay field, so why didn't it spin the tires? What happened to all the power the V10 was supposed to have? This did not happen only once, but twice, kind of embarrassing backing down the hill with everyone watching. Pulled fine once I got to the road and I haven't noticed any ill effects from this. Is this normal, would this have still happened to a diesel motor?

 

Pull the tranny dipstick. If it smells like burnt toast, then your tranny is. That DEFINITELY sounds like a tranny issue. I'd suggest a flush and a checkup. With a failing tranny, YES, a PSD would also have stalled on the hill.

 

Wouldn't I have seen some jumping of the tach if it was the transmission?

 

No. If your tranny was totally shot, then that might happen. It sounds like, under a load, that something in the tranny isn't jiving. Your engine was still moving, and the torque convertor was still spinning, and you were still building pressure from the pump, but the tranny just didn't want to go. I'm not real familiar with the tranny behind the V10 (yet...), but I'll explain it in C6 terms, and that might correlate.
In the C6, there's a band about 1/16" thick lined on the inside with clutch material. As that band gets old and worn out, the clutch material wears off, and the tranny will start slipping, like yours did when it 'wanted' to go up the hill, but didn't. Depending on how many of your 125k have been earned under heavy use, it may just be time for a rebuild. Good traction, 4-lo, and first gear really shouldn't have been a problem for your truck, even pulling 3 tons behind it. I've hauled far more with much less without a hitch. How has it been since then? You may also want to post under the 'transmission' forum. There's more help than I can offer there. Really, from what I've heard, 125k miles is almost living on borrowed time anyhow for an automatic, especially one that's run thru its paces on a frequent basis.

 

Seems to be running fine since that episode. Fluid looks good, I'll check out the transmission section to see if they have any advice. Thanks!