ATF +3/+4............ What's a guy to do?

[Greenleaf]

I will change my ATF but only find the +4. I also find the "Universal" ATF Semi-synthetic, which covers 75% of auto trannies.



Should I drain the 6qts of +3 that is in there when I drop the pan/filter and add 6 qts of +4?



Should I drain out all 12 quarts of +3 (somehow) and filler her up with +4?



Should I stop performing oil changes and run the +3 in there till the trans burns up then begin to use the new +4 w/my rebuild transmission?



Should I use the "universal" oil?



+4 says it takes place of the +3 so it may be ok to mix them?



How about full synthetic +4? Can I mix that with the old +3.



I can only drain off 6 quarts w/an oil change. She holds 12 qt



Should I switch to Dexron III or IV like DTT recommends?

 

[AKaiser]

You'll have to dig a little, but there is a description of the method I used to do a 100% replacement of the old ATF when I put in Amsoil ATF in my old 99 gasser. It involves removing thing transmission oil cooler line. Suggest you try doing a search on here and set the timeframe to "any date. "



Here's one that might shed light on it (searched for "transmission fluid replace")



https://www.turbodieselregister.com...t=162406&highlight=transmission+fluid+replace

 

[JLEONARD]

+4 says it takes place of the +3 so it may be ok to mix them

They should be compatable like that.

I wouldn't mix regular and synthetic though.

 

[KOG]

They are completely compatible. Change as normal. +3 is still available, but limited and high priced now. I just bought 2 gallons today ($56, a robbery, +4 is $16 a gallon now) to change back into a '94 Caravan 4 speed that's freshly rebuilt. Chrysler says that you'll get converter chatter on lockup using +4 in the 99 and older Caravans only during breakin. I figured that since we'd been running +4 in 9 of them since it came out that it would be fine. It wasn't. Chatters going into gear and on 1-2 shifts. So it's going back to +3 for about 10-15K for breakin.

For all other applications +4 is a superior fluid.

 

[tugboatphil]

Scott,



There is an article in the newest magazine that talks about how to do a full flush during a transmission fluid change.

 

[Kiohio]

And here I thought only Fords had the chattering transmission issue LOL



KO