91 Rodeo Transmission

Have 140K with no trouble, stopped at the lights, went to take off got a small clunk with a jerk, transmission took off very slowly. If I drop it down to 1st and manually shift up through the gears it seems to accellerate normally if I leave it in drive takes a long time to get to 30 after that runs normally, Any ideas where to start?

What your maintenance schedule on that tranny? Recent fluid & filter change?

Last Servicw was 20 K miles, so due another soon.
Am tempted to do filter and fluid change anyway.
Took it for another test drive, got about 2 miles with no problem then reverted back to slow acceleration, seems to be slipping only in D. Can accelerate normally in 1st?? Added question. Where can I find which model Transmission I have, Parts code is RMQ??

Last Servicw was 20 K miles, so due another soon.
Am tempted to do filter and fluid change anyway.
Took it for another test drive, got about 2 miles with no problem then reverted back to slow acceleration, seems to be slipping only in D. Can accelerate normally in 1st??So it seems okay if you shift manually? That could be an indication that your alternator going bad causing the tranny to act up.

Checked alternator, getting 14.5 V to ground, was changed 12 months ago.

I have an situation that is similar on my 92 4x2 rodeo. if i don't let it warm up the tranny may go into limp mode and lock itself into 4th gear. i restart and i'm fine, you may have a problem with one of your solenoids or the chip controlling the X-msn. if there is a fluid blockage that may cause the problem as well. alternately there could be a blockage in the valve body that reasserts itself when the vehicle is driven. in that event i recommend a full flush and filter change. let me know what you come up with.

What brand of alternator did you swap in there?

Believe it or not, your alternator very well could be contributing to the problem - any voltage shortage (even in the slightest) can send these Rodeo's on a gremlin chase. They HATE and will act strange if they can sense a weakness any where in the voltage system.

Double check your alt and battery under load. Then double check all your grounds, including your battery cables.

Another thing, I had the pleasure of owning a '91 Rodeo auto for 11yrs, the only somewhat expensive thing that happened to that rig after 150k carefree miles was a computer chip went out in the transmission. I somewhat recall the initial sign was very slow acceleration followed, within the same day, of coming home in reverse - that was the ONLY gear that would work after getting 3 miles down the road.

I can't tell you whether or not it's the same issue you're experiencing because mine occured all in the same day and within just the 3 miles of leaving home, there was no gradual signs of symptoms, it just shifted real slow at one light, then at the next light it wouldn't move at all, except in reverse.