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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

What weight for my tranny and rear diff ?

  • Thread starter Thread starter Killa
  • Start date Start date Dec 14, 2007

Killa

Active Member
Jul 9, 2007
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Dec 14, 2007
#1
  • Dec 14, 2007
  • #1
I been using RP on my tranny and rear and final result its a POS oil. Please recomment me none syntec fluid for tranny and rear diff. I heard that in the rear its require some special additive , what this call and where can I get it ? thanks
 

CobraRed_96_GT

Active Member
May 20, 2006
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39
UCSD/La Jolla
Dec 14, 2007
#2
  • Dec 14, 2007
  • #2
god RP sux. read this for rear end: http://www.performanceoiltechnology.com/Gear Lube White Paper.pdf
for tranny use a Mobil 1 synthetic or Mercon V
 

Brute03

Member
Mar 20, 2006
232
0
16
Dec 14, 2007
#3
  • Dec 14, 2007
  • #3
the additive you want is friction modifier, it's already included in some synthetic gear oils though
 

BennyBlown2v

New Member
Dec 9, 2004
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0
Carmel, INdiana
Dec 14, 2007
#4
  • Dec 14, 2007
  • #4
You're supposed to use ATF in most manual transmissions. NOT transmission oil. I use Mobil 1 in the trans and in the rear end. Their full synthetic gear oil @ 75w140 has friction modifiers built in - I've had better luck with that than the motocraft oil + friction mod.
 

Killa

Active Member
Jul 9, 2007
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Dec 14, 2007
#5
  • Dec 14, 2007
  • #5
recomment me none syntec oils.
 

2013 Geee T

Founding Member
Sep 25, 2002
805
5
19
Oak Park, CA
Dec 14, 2007
#6
  • Dec 14, 2007
  • #6
I just changed mine with the Motorcraft factory stuff (75w140 I think) and the 4 oz bottle of friction modifier. Works fine for me.
 

BennyBlown2v

New Member
Dec 9, 2004
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Carmel, INdiana
Dec 14, 2007
#7
  • Dec 14, 2007
  • #7
KillaGT said:
recomment me none syntec oils.
Click to expand...

Synthetic is indicated for the rear end by Ford, they DO NOT recommend using a non-synthetic gear oil. Synthetic good!
 

CobraRed_96_GT

Active Member
May 20, 2006
1,421
4
39
UCSD/La Jolla
Dec 14, 2007
#8
  • Dec 14, 2007
  • #8
think about it, your rear end doesnt have coolant passing by it or being directly cooled like the engine and tranny. It's a closed system, therefore heat that's built up pretty much stays there. You dont want an oil like mineral that breaks down bonds after extended periods of heat, synthetic is the take all champ at handling high temps. Just dont use a sythetic that has a detergent in it
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
17,934
224
Massachusetts
Dec 14, 2007
#9
  • Dec 14, 2007
  • #9
KillaGT said:
recomment me none syntec oils.
Click to expand...


Rear end on 99+ cars unfortunately is synthetic fluid only. There is even a tag on the doff cover that says so. It's 75W-140

I use Mobil 1. $15quart x 2 bottles
 

Killa

Active Member
Jul 9, 2007
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49
Dec 15, 2007
#10
  • Dec 15, 2007
  • #10
I heard knock on second gear pulling and and buzzing noise when stay in third ? should I check the fluid or what the knock for ?
 

fast97gt

Active Member
Jan 2, 2007
1,082
2
49
north carolina
Dec 15, 2007
#11
  • Dec 15, 2007
  • #11
KillaGT said:
I heard knock on second gear pulling and and buzzing noise when stay in third ? should I check the fluid or what the knock for ?
Click to expand...

change the trans fluid and use a mercon5 automatic trans fluid . for the rear you can use the 75w140 gear oil *note all 75w140 is synthetic and does not require friction modifier with it*. you can also use the 80w90 gear oil with the modifier . i use this method cause its cheaper, $4 bucks for the oil x2 and 6or7 bucks for the modifier, and works great compared to 14to17 bucks a quart for the 75w140.
 

blackfang

Founding Member
Dec 17, 2001
1,290
1
39
Richmond, Va
Dec 15, 2007
#12
  • Dec 15, 2007
  • #12
Mobil 1 gear oil with friction modifier and RP in the motor and trans. Haven't had any issues. In fact the grinding of my transmission is now gone since using RP
 

Killa

Active Member
Jul 9, 2007
1,006
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49
Dec 15, 2007
#13
  • Dec 15, 2007
  • #13
what store do i get these fliuid cheap ?
 
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