6 is a replacement for 3...I used the stop slip and it is doing it.

 

high milege atf is $31.20

 

is that for all gm trannys?

 

Do a filter and fluid swap but if that don't take care of your problem or make it worse then a rebuild is your only answer. You can honestly drive on a bad trans for years (my trans lasted 5 years with slippage) but one day eventually it wouldn't go into first or any gear for that matter. A cheap rebuild or a junk Trans swap can be cheap (around $700) but do remember you get what u paid for.

 

do what the manual says if it says 3 use 3 anything else would hurt in the long run

 

Dexron VI is not a replacement for Dexron III. They have different viscosity ratings and the VI is too thin for a trans designed to operate with III fluid. The high mileage fluid has an even higher viscosity rating and helps to increase line pressure for better shifts.

The Castrol high mileage fluid is only $7.50 at autozone.

I speak from experience. at 197k miles, my trans began to slip again. It did the same at 100k miles and I did the fluid and filter change with Dexron III. all was good then. At the 197k mile fluid and filter change, I took the advice from a few here and used the Dexron VI. And although it did help, it did not fix the problem completely, so I dropped the Dexron VI and went back with the Dexron III. Things improved but with the fluid in the converter still thinned from the Dexron VI, my problem wasn't completely solved. So i sucked 24 oz.'s out and added 24 oz.'s of the Lucas trans conditioning fluid. That improved the performance but it still isn't quite perfect. Lucas says a second bottle may be necessary and I have purchased one but haven't put it in yet. I suspect it will restore the thinned fluid to it's needed viscosity.

But the best solution is to NOT use Derxron VI and thin the fluid in the first place.

VISCOSITY IS EVERYTHING TO A TRANSMISSIONS PERFORMANCE.

 

I think I put in dex 6 on my SSEI 03 bonne at 50k and 112k it never slipped that I could feel.,yea viscosity is king.

 

I got 6 qts of high milege gtx oil and got 1 stop slip from lucas...

 

Avendo..
A fluid filter change may help..and it may not.
Unfortunately,
The transmission on these cars are the weak point.
Generally speaking between 80,000 and 120,000 is when these transmissions start to fail. and that's under "Normal" driving conditions.

These transmissions weren't built for racing. in any way shape or form..
I would recommend driving it easy and you may luck out and get it to last a little longer .It usually starts with hard shifts.. However, if your experiencing it slipping.. I'd have to say it wont be long before a rebuild/swap will be in order.
I do know from experience...
A rebuild will run between $1,600 and almost $3,000 depending on where you live and the shop that does the work.
Good luck!
I hope things work out for you with the information you have received from experienced members.

 

Its not really slipping really...just making sure it doesn't and I have done my drag racing when I was a kid..
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