Wrong Transmission Fluid put in my PreRunner!

I have 88,000 miles on my 2005 Tacoma V6 and decided it was time to have some preventative work done including a automatic transmission fluid and filter change. I have not had an ounce of trouble with this great truck until now.
I took it to a well established local shop (not Toyota) which performed the service. Picked up my truck, drove it for about 40 miles and it then began to shift hard or even bang into a gear now and then. I took it back and explained the problem, they called me back and said they had installed the wrong type of transmission fluid so they drained it and refilled it with the correct Toyota oil. I drove it about 50 miles and it is now worse than the first time. I am of course going to take it back but am wondering if they ruined the transmission and how I should handle this?
Any input is appreciated.
Thanks

 

Jiffy Lube did that to my dad. They bought him and installed a new transmission.

Took some writing and fighting with a regional corporate office, but they didn't push to hard.

 

That's what I have been reading online, I hope this doesn't turn out to be a long issue! Thanks for the Information, I greatly appreciate it.

 

Complete flush or a just a drain and fill?

 

From what I was told just a drain and fill.
Thanks,
Lou

 

Tires Plus did the same thing to me. I brought it to Toyota to diagnose and fix it. 2005 Tacoma 65,000 miles started running real rough the next day. Cost them $3800 for a brand new transmission plus a rental car for the week. I have 145,000 miles now thinking about taking it to them again.

 

Before jumping to the conclusion that it needs a new transmission, start with the simple things. Call the place and calmly ask what fluid they put into your transmission. If it's the right stuff, check the fluid level. Incorrect fluid level can make the transmission shift weird.

If it's the wrong stuff, I'd try having Toyota do a complete flush with the correct fluid. I'd also hand the bill for the work to the place that screwed up the first time by putting the wrong oil in. If you get the correct fluid in the transmission, and it's still acting up, then you might have some damage that won't be easily or cheaply fixed. If that's the case, get ready to do battle with the place that did the oil change in the first place. Because it was only a drain and refill, they likely only drained about 3-4 quarts of fluid and replaced it with the wrong stuff. The transmission holds around 17 quarts I believe.

 

If they are only doing a drain and fill then all these fluids are getting intermixed. You now have a combination of old fluid, incorrect new fluid, and correct new fluid. Your system needs to be completely flushed and cleaned now before it is refilled. Hard to believe that a few miles on the wrong fluid could ruin the transmission, but