I called qk. lube , for service on my trk., the guy said because the newer trks., require syn., fluid he flushes & refills w/ new syn., fluid . Do ido it, or stay w/ dextron???trk., 91 d350, auto.

 

Don't flush it.

Use whatever fluid makes you happy.

 

I must agree on the dont flush. Just change the filter and refill with what ever fluid makes you happy. There is something about flushing that jut bugs me. I guess its cause I never really hear about people who just change oil and filter and go. But seems when people flush, then change and go leads to problems. I think that if it is not running free in regular use then why not it loose with a flush. But that is just my 2 cents......

 

Faith, Benb, so you think the synthic trans fluid will be ok?? thanks .

 

yeah synthetic is good, Valvoline ATF +4 is what i used before, and its synthetic.

 

I used wallmart cheapo stuff. Works great.

 

I run synthetic as well, same as blacky. Valvoline ATF +4. $6 a quart where I got it from. I don't see an advantage though. I guess you could run it hotter than non synthetic?

 

Yeah it is a bit pricey. Synthetics will last longer, and it flows much easier in the cold. I'm gonna go with amsoil after i put my new to me 47rh in.

 

I used to run the Amsoil ATF ($$).

These days I run the cheapest ATF-4 the parts house has. Works just fine.

 

I was pretty sure you can't use Dexron in a Mopar trans because the mopar clutches are different.

 

dont let any shop flush any part of your drivetrain unless you are positive they wouldnt screw you over.

 

I am a firm believer in you get what you pay for. With that said lets face it dollars and cents are what make things move. Go with what you can. Any new/clean oil is better then old burnt stuff. The biggest advantage to syn. is they hold up better to the regular and extreme abuse. I have seem 2stroke motocross bikes run almost a tank of UNMIXED fuel before the engine goes. It was being ran with amsoil prior. But if you go with DINO change often if you go with syn. you can go little longer but just watch it.

But thats my 2 cents all in all its your choice.

 

Brandon, most older torqueflites were all dex III and absolutely not compatible with the dex/merc mix fluid. Most of the newer stuff is all +4

 

Well if you go to a 1st gen Cummins/Auto truck and pull the dipstick out, it says right on it to use ATF+ .

 

me too.

Plus, if your only dropping the pan and changing the filter you are only getting 1/2-3/4 of the fluid out anyway so whats the point of adding synthetic to what ever is still left in it.