AT545 What Trans fluid do you recommend?

[Matl0c]

Hey all,


I have looked through most posts regarding the AT545 and I haven't saw what type or kind of trans fluid people are using. I will be adding a cooler and changing the fluid and filters and was curious what people have been using.

[EastCoastCB]

Mine had a fresh change when I picked it up but I'll be draining it and refilling with Transynd. The standard stuff for a 545 is dex 3.

[Matl0c]

Thanks! I am thinking the same

[EastCoastCB]

Its around $45-$55 a gallon but its synthetic. In Fl it actually says in the school bus regulations and that all school buses must run transynd.

I got a cooler from Tango that he didn't need and plan to install it when I do the fluid change. Its a beefy unit made by Earls. He made me a deal on it but new they're around $400.

[Matl0c]

I got a pretty decent deal on this cooler from a local shop I used to deal with. Should work for me.


https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[Booyah45828]

Like charlie said, dexron 3 was the standard fill ages ago.

I recommend sticking with it. It's good enough for the job and you can get it from almost anywhere (parts store, hardware, grocery, gas station, etc.)

Transynd is a great fluid. It's a premium synthetic which will last many many miles and run cooler doing it. But for most, it's not necessary and just wasted money.

Some people have used John Deere hy-gard hydraulic fluid. I've never done it so I can't recommend it.

Some districts even used engine oil with allison's blessing

[Johnny Mullet]

I used standard Dextron/Mercon with some Lucas in mine. Video How To here........

https://www.youtube.com/watch?v=AMUT_wk63qM

[Matl0c]

Thanks for the help! Should be installing the additional cooler this week and changing the fluid

[Wuzabus]

OMG TY TY TY FOR This post and the link to the tranny cooler. I just hope my differential is that easy to drain. Transmission seems easy enough.

---WITHOUT WHEELS. IT WOULDN'T ROLL...

[s2mikon]

I have used 15w40 since the 1980's in 500,600 and 700 series Allison transmissions with good results.