Transmission "bucking" when going into OD

[Mike_F]

Or, at least I think its the tranny. Between 40-50 mph right after the final upshift the 2000 V8 123,000 miles Explorer bucks as if there is a miss in one or more cylinders. Over 50 things smooth out and it runs fine. Since I've replaced three transmissions in two previous Explorers, I'm assuming the problem lies there. If it is does this mean another new tranny or might it be something fixable? You'd think I would have learned by now to stay away from Explorers. I must be a glutton for punishment.

 

[toypaseo]

Check your fluid level?

 

[Mike_F]

Yes but not until after I posted. Duh. It was down a bit (1/2 - 1 qt) so I added some more fluid. It was nice and pink no burnt smell. After a little more research I found that this is not uncommon and is known as shudder. I added a couple ounces of "Shudder Stop' (or something like that.) I'll see tomorrow how things are.

 

[96eb96]

If the fluid is over 50K and not burnt it is probably time to drop the pan, replace the filter, and pump in and replace about 15 qts of Mercon V thru the cooler. Very common issue with the 4r70W. Just did it on a 98 GMQ, shifts like a brand new car, has the same trans. You can verify it by touching the brake, if it goes away it is torque converter shutter. The shudder fix may do the trick though.