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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

Diff and Trans Fluid Change...Royal Purple?

  • Thread starter Thread starter 91LX_5L
  • Start date Start date Sep 20, 2007

91LX_5L

Founding Member
May 13, 2002
1,943
0
36
British Columbia
Sep 20, 2007
#1
  • Sep 20, 2007
  • #1
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

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Sep 20, 2007
#2
  • Sep 20, 2007
  • #2
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

My assy trans to myself
15 Year Member
Feb 22, 2007
5,125
3,091
214
Cedar Rapids, Iowa
Sep 21, 2007
#3
  • Sep 21, 2007
  • #3
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!
 
Z

zZsKyZz

Member
Dec 1, 2005
503
0
17
Sep 22, 2007
#4
  • Sep 22, 2007
  • #4
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

My assy trans to myself
15 Year Member
Feb 22, 2007
5,125
3,091
214
Cedar Rapids, Iowa
Sep 23, 2007
#5
  • Sep 23, 2007
  • #5
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

Founding Member
May 13, 2002
1,943
0
36
British Columbia
Sep 24, 2007
#6
  • Sep 24, 2007
  • #6
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

New Member
Jan 27, 2003
2,244
0
0
Glenview,Il
Sep 24, 2007
#7
  • Sep 24, 2007
  • #7
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

Member
Apr 10, 2004
309
0
17
Sep 25, 2007
#8
  • Sep 25, 2007
  • #8
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

My assy trans to myself
15 Year Member
Feb 22, 2007
5,125
3,091
214
Cedar Rapids, Iowa
Sep 25, 2007
#9
  • Sep 25, 2007
  • #9
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.
 
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