another problem

i just put on a new exhaust. after taking it out for a test drive, the rodeo shakes when i hit overdrive...not any of the other gears, just overdrive. It seems to go away after a few miles, but when i accelerate from a stop, i go through all the gears and when overdrive hits, the whole vehicle shakes pretty bad. Seems like the front end, but cant really tell. I had this problem before changing the exhaust...thought it was the problem since the hangars all broke...it wasnt. any ideas? i checked the oil and it was low...gonna change it tomorrow. The tranny fluid was clear and full.

1995 rodeo 4x4 3.2l

Check your driveshaft....specifically your carrier bearing. Make sure there's not too much play.

Also lubricate your driveshaft thru the zerks....helps a lot.

I know you've had your rear differential replaced, IIRC, how old's the fluid now?

the rear fluid is brand new....it still leaks and i refill it monthly. it was just done a week or so ago. I'll lube everything up today. almost seems like the shake is in the front..

after crawling around the ground underneath my p.o.s in 4 degree windchill, i did notice that the driveshaft moves quite a bit at the center bearing...i suppose this means i need a new one. all the bolts were tight and none missing. The play wasnt too bad but i could see where it would make the car shake. If the play is normal, i'm stumped as to what would make the car shake.

I've never had to replace mine....outside of having a defective one when I first bought it 190k miles ago. Dealer replaced it under warranty. I know if there's more then 1/2-1" play then it could be shot....have Firestone or someone take a look and see what they think.

Are you sure it's not a problem with the tires, shocks, or wheel bearings?? Ball joints come to mind as well...all very typical on a truck as old as ours.

You mention it to be a p.o.s; I know you've had a lot of issues with yours....thought you were gonna sale it a while back?

i was but i need it for the 4x4...i have to be at work even if our roads are under a level 3 snow emergency ( which means nobody except emergency personnel can be on the roads )

2 new questions:

#1 i added some sea foam to my engine with new oil...do i need to drain it or can i leave it in there for awhile?

#2 while looking at my front end trying to figure out the shaking problem, i noticed my drivers side front tire can move a little bit (by grabbing the top and bottom of the tire and pushing in and out) does this mean i need a new ball joint? the movement was very little....is it a pain to change out?

1. i wouldn't go more then a couple hundred miles without changing the oil

UPDATE:

i finally found out what the vibration was...the hangar that is on top of the catalytic converter completely rusted off the converter AND underneath the rodeo...so when the rpms drop in o.d, the catalytic converter and front part of the exhaust shake violently. Shook so bad it almost broke the new muffler and taoil pipe hangars...so now i have to fabricate something to hold the catalytic in place and find a place to bolt it to on the underbody. should be fun....:banghead:

Interesting....would've never thought.