Diff and Trans Fluid Change...Royal Purple?

[91LX_5L]

Royal Purple is about the best I can get out in my neck of the woods. Just wondering what I need excatlly for the diff and what i need for the trans? What weight oil for the diff, need friction modifier? Trans just royal purple ATF or what?

Thanks

 

[5spd GT]

I used RP ATF Dexron/Mercon III if I recall...

I never had a grinding problem with my 94/95 transmission for 2.5 years. I did a rebuild with a couple other little things (longtubes over shorties/ported lower intake) and added the RP in the tranny.

I believe it was my second trip to the track after the addition and my transmission started grinding in 3rd and 4th.

Do I think it was due to the RP for sure? No

But it did make me a little nervous on doing it later...

 

[95BlueStallion]

Ever since I put Royal Purple in my tranny, I have had a 2nd and 3rd gear grind... Im gonna drain it and put regular merc III back in and see if it goes away. I never had the grind before, and the only other thing that may be causing it would be my pro ripper shifter I put in when I changed the fluid... Maybe it allows me to shift too fast? Short story long, I dont like the royal purple tranny fluid!

 

[zZsKyZz]

Royal Purple is junk. The reason it's expensive is because they sell it as a "Performance" product and everyone thinks it's great. They don't even give SAE ratings on their oil like Valvoline does or Castrol.

If you want good synthetic oil, stick to Mobil 1.
As far as normal oil, I use Valvoline synthetic blends.

Read up a little on oil, you'll learn little things on what to look for. By no means is all oil the same.

 

[95BlueStallion]

I dumped my royal purple and threw in valvoline extended life merc III and my second and third gear grinds are gone... Im so happy, I thought my syncros were on the way out, but it was aparently just that the royal purple was too thin or something. Problem solved.

 

[91LX_5L]

well I ended up putting in royal purple in the trans and rear, wish I read this first. oh well it was the only 'performance' trans oil I could get around here, wanted amsoil but didnt get it. i havent had any problems so far?

 

[go-stang5.0]

I run amsoil 3-4yrs. and its problem free. Havent changed it since but I will when I do the clutch soon. Point being its good and lasts a while.

 

[shelbe67]

have you guys used amsoil motor oil? just wondering a buddy of mine has and he claims that he burned through 2 qts since his oil change and his truck has never done that before. He does drive like a jack---

 

[95BlueStallion]

Ive heard different things from different people about all kinds of fluid. I think the best way to find out is to try it for yourself... I tried the royal purple tranny fluid and it didnt work for me, but Ive heard others say that its great. You may have great luck with it.