1995 Toyota 4Runner 3.0 auto, hot trans surge

change fluid and filter,if in stop and go traffic take it out of od,this will heat up the tranny,od is mainley for open road trips.

Ok, removed Pan & cleaned & replaced screen, minimal particles, normal wear, only 75K on vehicle. After servicing did complete fluid switch at friends Auto shop. Condition still present, Mechanic thinking it's a mis-fire in motor, still no codes present as we also checked with OBD-2 Snap-On Scanner yesterday as well. Still stumped. Only when hot at medium throttle-worst under load like going up hill, present at sift from 2-3 & in 3rd. If i shift manually will not happen as shift point higher??

OK,have the cat converter checked,it may be cloged,you can do the drill test yourself,drill a 1/8 hole in down pipe before cat converter,drive it see how it runs if problem goes away you know it is the cat converter,if not another test done,put a screw in hole or weild it.

Ok, took O2 Sensor out in front of Cat Converter, drove for 45 minutes and Condition still present. The first time of the day you drive it it takes 30-45 minutes before it will start acting up. Once you have driven problem present much sooner. Drove yesterday in the mountains for several hours on dirt roads, with the tranny locked in 1 or 2 had no issues, as soon as you put in D it will surge again?

you might want to have a compression check done on the motor.

Ok, so it get's even weirder! My Speedo was jumping a little also at lower speeds. I decided to unhook it just for kicks & that I am running out of things to try and gollie, condition gone.....so far. Perhaps my tranny speed sensor and the info the computer is getting from the speedo with it being irratic is confusing the electronically shifted trans? I don't know but it glides down the road, no bucking. Gotta a 300 mile day tomorrow so we shall see...stay tuned & thanks.

ok it may just need a new speed sensor,or the plastic gear is worn out the one where the cable hooks to.

Well, so $126 speedo cable later & problem gone! Apparently there is a Speed Sensor in the Head unit of the Speedo as well as on the tranny. If they both do not get similar readings it confuses the computer & that darn electronically shifted trans will act up....................go figure. Thanks for your imput.

I have a question. Did you try to put your cruise control on at all? If I put mine on and it like down shifts and sits around 3000 rpms. Im hoping maybe this is the problem with mine. It kinda feels like it is put-puting when I drive it and my gauge slightly jumps. I just did a tune up as well as fixing to check the timing. Thank you.

This is all pretty interesting. My 1995 4runner also has some of these issues. When it is cold, my speedometer does jump a bit, and it I use the cruise control while it is cold outside it jumps in time with the speedometer (even after the vehicle is warm). I will look into replacing the cable and gear. How difficult is this to fix yourself?

Also, should I look for something toyota branded or off brand will work just fine?