Originally Posted by TraditionalTanner

Hello friends. I have a 97 4runner 3.4l auto trans that has been in the family and has made wonderful family memories across the u.s. about a year ago my trans cooler unit failed and it backflushed trans fluid into my coolant and vice versa. It was an on the side of the road, thousands of miles away from the home repair. After about $600 worth of trans fluid, the tranny was flushed out and I installed a new radiator(trans cooler is permanently attached to the bottom of it). No issues, drove excellent. After arriving home after some time had a CEL light come on, ran it and it was throwing a code for a shift solenoid. Asked a good mechanic friend and he said if it wasnt causing any issues, just keep rolling. Work was busy and like a fool I continued on. Fast forward a year and I am heading down the interstate a few weeks back(solenoid light still on) and the tranny feels like its slipping. A little later into the trip I see a auto trans temp warning light come on with the strong smell of trans fluid. I want sure exactly how long that light was on in that few hour trip as I had a photo placed on the dash and it wasnt until I smelled the transmission fluid that I removed the photo as I had a gut feeling it had a light on
I immediately pulled over off the highway and met her cool down. I was 4 miles away from my destination. After a length of time permitted for cooling I proceeded down the highway until I arrived at my destination, allowing her to cool off again. On the trip home the a/t temp light never dis come back on but the strong smell of tranny fluid was prevalent with the slippage feel if I really stepped into it. I usually do my own repairs unless I am super busy with work and at the present moment I happen to be in the event I take it to a trusted mechanic. He is booked out like 2-3 months so I took it to a secondary mechanic(dont know a ton about him but hear good things). He said we can throw a new solenoid kit in($450), new ATF fluid and a new seal for $675. But he later got ahold of me and said the ATF fluid was black and smelled burnt. I will testify and say that the ATF fluid probably needed replacing prior to all this occurring. We were going to replace it anyways when we got home after our trip where the trans cooler unit failed but work picked up. My question is, do I go ahead and swap out the solenoids, hoping it will be a remedy or replace the entire trans with a used one pulled from a salvage yard?The mechanic the 4runner is at thinks the transmission MIGHT be bad based solely on the burnt smell of the ATF on the dipstick and the black coloration of the liquid. Please, any feedback would be much appreciated. 🤙