Your description is real confusing but mixing new and old transmission fluid is not uncommon. Torque converters haven't had drain plugs for decades. The only way to get the old fluid out of them is with special flushing machines.

If it's not shifting correctly, that is a different issue. It sounds like someone already tried a flush thinking that was going to automatically solve some mechanical problem. The best approach is to let a mechanic at a transmission shop drive it and give you an opinion on repair cost.

Answered by caradiodoc (expert)
17,655 answers provided

I know what you mean I was very confused when he said that to me as well. He also said that he has been driving it for 8 months and never had any issue with it. I asked him if it felt like it was going to slip and he said not just switching between 2nd and 3rd i have to let off the gas.

Response from bbg
1 question asked

On my 99 Grand Cherokee when it did that I changed the output shaft speed sensor and all was fine.

Answered by racefan966 (expert)
4,893 answers provided

I have had a few people tell me that, is that easy to fix/change? I dont know that much about jeeps.

Response from bbg
1 question asked

Oh yea on the drivers side of the trans just above the pan

Answered by racefan966 (expert)
4,893 answers provided

thats great, sould i still get it flushed?

Response from bbg
1 question asked

If the fluid looks other then red or is not the correct fluid then yes, it should have ATF+4 in it.

Answered by racefan966 (expert)
4,893 answers provided

would it still be like a red color if he mixed old with new?

thank you so much for helping me.

Response from bbg
1 question asked

Yes it would be. So if your not sure if the correct fluid is in it then I would flush it anyway.

Answered by racefan966 (expert)
4,893 answers provided

okay thank you so much for helping me :D

Response from bbg
1 question asked