94 Corolla tranny problem

250,000 mile running perfectly except for frequent problems with slipping tranny, O/D light coming on without pushing the shifter button, cruising down the road at highway speed and suddenly rpm shoots up and tranny slipping. Slowing down will usually correct the problem and I can continue along. Sometimes I can go miles with no problems, other times I can't get out of the driveway without the O/D light coming on and experiencing the slipping.

Time for a tranny replacement or is there something else going on. Can't tell you when the fluid and filter was replaced. Levels are ok.

Try flushing the tranny with new fluid. Sometimes that makes all the difference. Take off the pan and replace the filter also. It may be partially blocked.

i do not know alot about transmissions esp. auto which i assume you have. but *most* decent tranny shops will tell you what the problem is for free along with a quote. if you have no money and just need it to work for a while ( i suggest sawdust in the tranny as a last resort.) i did that with a ford explorer and got around town no problem but it requires frequent flushes and repacking of sawdust prolly not worth the effort but it was the 4th tranny in that explorer and i was sick of it, the sawdust lasted longer than the last transmission (i hate ford explorer transmissions). DO NOT SELL CAR WITH SAWDUST IN IT unless you notify buyer and put it in writing that it is a known problem with the car and have them sign it. the best option is to do a filter/gasket change and flush and refill the fluid let the fluid drain into a clean pan and check for chunks of gears and whatnot, whatever chunk you find is probably the problem. or take it to a decent trans shop and have them tell you whats wrong with it for free. good luck