Ok, when it shifts into OD below 45 mph it will make numerous attempts to shift back into D.......like in a matter of a split second it'll upshift then shift hard back into OD, then do it again, and again til i get above like 45 mph then it stops and does perfectly fine after that. im maybe a qt low on tranny fluid and was wondering if that could be the problem...if it is, what kind of fluid doi put in it? ATF +4?

 

ATF +4, yea, but what it sounds like is you have a bad main ground from your batteries or the wireing harness to your tranny is chaffing through on a hanger and grounding out.

this is a common problem on 98-01 trannies.

 

interesting....so trace the ground wire from both batteries to the tranny and see if anything's gone wrong?

 

yup. . .if there is some corrosion knock it off and clean it up. then trace the wireing harness from the tranny and make sure the wires are not rubbing on anything.

 

oh by the way where is this hanger located?

 

not real sure. . .you just have to look for the transmission wireing harness and follow it.

 

cool thanks drew..... im gonna try some of ur brew too, see how that does with mileage and torque.

ive called every tranny shop and described it to 'em, they said its some kind of pressure solenoid or pressure governor. i dont want them to take me for $600 if all i gotta do is reposition a harness. its not slipping in the least bit...it shifts firm..... but for some odd reason it just wants to try to kick down a gear a few times while in OD up until i get to 45 mph. its really hard to describe but once i hit OD and start feelin that torque, the RPMs jump really fast liek its grabbing D and then drops back into OD, takes less than a second for that to occur. does it a few more times then stops after 45 mph.

now, if i take off hammered down all the way to 70 mph, it wont do it at all.

 

this was an issue I read about over at TDR. there were always two culprits when the tranny would hunt like that. it was found that the corosion on the main ground prevented good grounding for the transmission, and in same cases the main wireing harness was rubbing just right on a hanger causing some of the wires to chaffe and ground out. when you check the wireing harness, look at it closely you may not be able to see where the wire is grounding out, however a 10c roll of electrical tape will fix the problem

Mayfair had a similar issue with his tranny hunting gears and the torque converter locking and unlocking. his main ground had some corosion on it, he cleaned it up and has yet to have an issue since.

 

is the harness on drivers or passengers side of truck? and exactly where is the main ground bolted, on the battery or the frame and where at on the frame?

my buddy just looked at it, drove it, said it felt like it had a shift kit put in it. ive only had it a week or so....plus its about a quart or two low tranny fluid in neutral with the engine running, so with a shift kit and a little low tranny fluid could that cause it too? i'm gonna climb back under after i find out where the grounding point yall are talkin about is located.

pictures????

 

My '01 used to have a similar problem, would shift back and forth between gearsat 45 and 55, and would be fine on hard accelleration. Had a bounch of shops say that they would start running tests on it for lots of $$, and they still may not find it. I finally took it to the dealer and they found that the throttle valve had play in it, so they replaced the whole assembly ($1200) Ran like a champ after that. They may have taped up the trans harness and ripped my off, I guess I'll never know.