Transmission slipping mostly while turning

[HaffaWaffle]

I have a 96 Park Avenue base model that is now sitting with a dead battery due to transmission problems. I bought the car a little over a year ago for only $800, So im pretty sure thats why the previous owners were selling. I am just wondering if anyone has any ideas or if i just need to get rid of it and move on. I put a little under 20k miles on it since I bought it. The car has 185,983 miles in all.

What happens is that when you turn left or right and accelerate, the transmission kicks out pretty violently. It also slips if you accelerate too fast.
I have been told by my mechanic that the transmission is shot and needs replaced. If that is so, where is a good place for a replacement trans? If i can find a replacement, I can get it put in for cheap.

 

[MelsRegal]

assuming you have checked the fluid level, have you tried replacing the filter and fluid? Your mechanic has a shop and doesn't know where to locally obtain a used or rebuilt trani?

 

[HaffaWaffle]

We have checked all fluids and filters, and the only reason I ask where to find one is just to get as many options as possible. He said he has a pontiac bonneville that has the same 3.8L engine and trans that he would just swap them. Since im no professional on the subject, im skeptical if it will even work.

 

[HotZ28]

The donor trans would have to be the same model/year (1996) 4T60E, not the later 4T65E from 1997 up.

 

[Ziggy]

Does it do this cold or warm? If only cold you could try putting Dexron 6 fluid in it.
It cured 99% of the problem for me (though not on a Park Avenue)

 

[HaffaWaffle]

Thanks, ill make sure to keep this in mind if we do the replacement.

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Does it do this cold or warm? If only cold you could try putting Dexron 6 fluid in it.
It cured 99% of the problem for me (though not on a Park Avenue)

It doesnt matter what temp, its pretty much guaranteed to slip either way.