What is the best transmission fluid for my cars?

I'm wondering which kind of tranny ATF is best for my cars. I currently own:

1990 GMC Vandura 2500, 350 cui TBI, TH700R4 transmission
1991 Pontiac Firebird Trans Am, 305 cui TPI, TH700R4 transmission
1994 Pontiac Trans Sport, 231 cui SFI, 4T60-E transmission

Now for the GMC and the Trans Am, the manuals tell me to use Dexron II
fluid. The Trans Sport manual tells me to use Dexron II-E.

I understand that Dexron II is not in production anymore and has been
superceded by Dexron III fluid. Now if I look e.g. at Valvoline's
product line, I can see that they have mineral ATF und synthetic ATF.
Now is synthetic ATF better for the transmissions or is it just more
expensive? Or would it be better to go with mineral ATF for the older
TH700's and synthetic ATF for the newer 4T60-E?

I don't know what's best for my cars. Suggestions welcome.

Markus

"Markus Klama" <markus@klama.de> wrote in message
news:caqf10$glb$1@online.de...
> I'm wondering which kind of tranny ATF is best for my cars. I currently
own:
>
> 1990 GMC Vandura 2500, 350 cui TBI, TH700R4 transmission
> 1991 Pontiac Firebird Trans Am, 305 cui TPI, TH700R4 transmission
> 1994 Pontiac Trans Sport, 231 cui SFI, 4T60-E transmission
>
> Now for the GMC and the Trans Am, the manuals tell me to use Dexron II
> fluid. The Trans Sport manual tells me to use Dexron II-E.
>
> I understand that Dexron II is not in production anymore and has been
> superceded by Dexron III fluid. Now if I look e.g. at Valvoline's
> product line, I can see that they have mineral ATF und synthetic ATF.
> Now is synthetic ATF better for the transmissions or is it just more
> expensive? Or would it be better to go with mineral ATF for the older
> TH700's and synthetic ATF for the newer 4T60-E?
>
> I don't know what's best for my cars. Suggestions welcome.
>
> Markus
>

Unless you could completely flush the transmission the synthetic would mealy
mix with the mineral ATF diluting any of it's synthetic advantages. It may
be a marginal help but unless you flushed and refilled with synthetic I
would stick with mineral and change it every 20k miles or so.

Brian

"Markus Klama" <markus@klama.de> wrote in message
news:caqf10$glb$1@online.de...
> I'm wondering which kind of tranny ATF is best for my cars. I currently
own:
>
> 1990 GMC Vandura 2500, 350 cui TBI, TH700R4 transmission
> 1991 Pontiac Firebird Trans Am, 305 cui TPI, TH700R4 transmission
> 1994 Pontiac Trans Sport, 231 cui SFI, 4T60-E transmission
>
> Now for the GMC and the Trans Am, the manuals tell me to use Dexron II
> fluid. The Trans Sport manual tells me to use Dexron II-E.
>
> I understand that Dexron II is not in production anymore and has been
> superceded by Dexron III fluid. Now if I look e.g. at Valvoline's
> product line, I can see that they have mineral ATF und synthetic ATF.
> Now is synthetic ATF better for the transmissions or is it just more
> expensive? Or would it be better to go with mineral ATF for the older
> TH700's and synthetic ATF for the newer 4T60-E?
>
> I don't know what's best for my cars. Suggestions welcome.
>
> Markus
>

For Trucks, I go with a good ATF like Valvoline maxlife ATF.

For Perfromance Cars I used B&M Trick Shift.

Regular cars get regualar dextron III.

Charles

On Wed, 16 Jun 2004 20:50:38 -0400, "NoSpam" <nomail@spam.not> wrote:

>
>"Markus Klama" <markus@klama.de> wrote in message
>news:caqf10$glb$1@online.de...
>> I'm wondering which kind of tranny ATF is best for my cars. I currently
>own:
>>
>> 1990 GMC Vandura 2500, 350 cui TBI, TH700R4 transmission
>> 1991 Pontiac Firebird Trans Am, 305 cui TPI, TH700R4 transmission
>> 1994 Pontiac Trans Sport, 231 cui SFI, 4T60-E transmission
>>
>> Now for the GMC and the Trans Am, the manuals tell me to use Dexron II
>> fluid. The Trans Sport manual tells me to use Dexron II-E.
>>
>> I understand that Dexron II is not in production anymore and has been
>> superceded by Dexron III fluid. Now if I look e.g. at Valvoline's
>> product line, I can see that they have mineral ATF und synthetic ATF.
>> Now is synthetic ATF better for the transmissions or is it just more
>> expensive? Or would it be better to go with mineral ATF for the older
>> TH700's and synthetic ATF for the newer 4T60-E?
>>
>> I don't know what's best for my cars. Suggestions welcome.
>>
>> Markus
>>
>
>Unless you could completely flush the transmission the synthetic would mealy
>mix with the mineral ATF diluting any of it's synthetic advantages. It may
>be a marginal help but unless you flushed and refilled with synthetic I
>would stick with mineral and change it every 20k miles or so.
>
>Brian
>
I agree with Brian. Change fluid regularly (I use 30k as the mileage
point). I've had mostly AT vehicles, both cars and trucks, since 1963
and have never had a trans fail. Good luck? Good maintenance? It is
what it is.
YMMV
FWIW
DFB
For email remove "_no_spam_"

> I don't know what's best for my cars. Suggestions welcome.
>

A true group IV synthetic such as Mobil-1 ATF will provide better protection
in high heat conditions than can the conventional fluids.

John