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

T5 Tranny Fluid & Rear End Fluid

  • Thread starter Thread starter ZachMorris
  • Start date Start date Oct 16, 2017
Z

ZachMorris

Active Member
Jun 21, 2017
143
15
28
Oct 16, 2017
#1
  • Oct 16, 2017
  • #1
Good morning,

I used the search function but i got alot of conflicting answers and nothing very recent. My 92 Notch hasn't had the fluid changed in probably 8+ years so I'm going to change the transmission fluid and the rear end. Rear end is an 8.8 Auburn HD 31 spline and the t5 is just a stock WC with a King Cobra clutch and FMS Billet steel fly wheel.

What do you guys recommend?
 

Dan02gt

mazing how much gas smell came from that tiny hole
20+ Year Stangneter
Mar 2, 2003
909
415
113
Greenville, NC
Oct 16, 2017
#2
  • Oct 16, 2017
  • #2
My T5 is going to need a rebuild or replacement soon. Main problem is notchiness down shifting into 2nd and it's noisy. Upon trying to find the best fluid to limp it along I found that Royal Purple Syncromax was far better than anything else. I also tried Amsoil, Mobile 1, and standard Dextron 3. The Royal Purple made a big difference in noise and smoothed out the shifts.

I run Mobile 1 in the rear end. It comes with the limited slip additive so you don't have to add friction modifier.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,255
17,939
224
Massachusetts
Oct 16, 2017
#3
  • Oct 16, 2017
  • #3
I use regular Castrol D3 ATF in mine after I rebuilt it. It shifts like butter and is silent.
 

fredfifty

5 Year Member
Nov 23, 2011
318
57
59
SF Bay Area
Oct 16, 2017
#4
  • Oct 16, 2017
  • #4
i went to the ford dealer and bought ford motorcraft synthetic 75w-90 rear axle lubricant, cant go wrong with ford fluids
 

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
Jul 20, 2014
4,739
3,188
203
Taylorsville ky
Oct 16, 2017
#5
  • Oct 16, 2017
  • #5
I use Super S 75w140 synthetic gear oil-has the modifier in it.
Been a while since I’ve had a manual trans-I think last time I used parts house branded atf with no issues
 
Z

ZachMorris

Active Member
Jun 21, 2017
143
15
28
Oct 16, 2017
#6
  • Oct 16, 2017
  • #6
Is there any filter that needs to be changed??
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,255
17,939
224
Massachusetts
Oct 16, 2017
#7
  • Oct 16, 2017
  • #7
In manual trans or rear diff? No. Just magnets on the drain plugs.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,301
1,643
214
Acworth, GA
Oct 16, 2017
#8
  • Oct 16, 2017
  • #8
Any brand of syncromesh is going to improve your transmission. I wouldn't go as heavy as gear oil (80W-90) in the transmission, they really aren't built for it. Honestly, I'd just get the parts store brand. I'm sure Royal Purple is the best, but I personally can't justify putting super expensive oil in a T5. Lots of different opinions on the gear oil for the axle. I put 80W-90 in mine. It's self changing, because the pinion seal leaks, and I just top it off every few years. Make sure you put the friction modifier in it.

Kurt
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
10,570
203
polk county florida
Oct 16, 2017
#9
  • Oct 16, 2017
  • #9
I am a big fan of synthetic rear gear lub. My truck has over 550k and no issues, just replaced the wheel bearing but honestly they still looked good.
I use royal purple in my t5 but if you change it every 25k or so it is likely a little overkill.
 
Z

ZachMorris

Active Member
Jun 21, 2017
143
15
28
Oct 17, 2017
#10
  • Oct 17, 2017
  • #10
I grabbed some Royal Purple Syncomax for the transmission and some Valvoline 80w-90 for the rear end. What are your thoughts on the Valvoline 80w-90? The reason I went for this is because I have an Auburn diff and I heard they require 80w-90....also the gentleman at Napa told me I did not require the friction modifier because the Valvoline 80w-90 states Limited Slip right on it.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
10,570
203
polk county florida
Oct 17, 2017
#11
  • Oct 17, 2017
  • #11
Go to ford and get the friction modifier, the gear lube is 'compatible' with limited slip I don't belive it has any friction modifier in it.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,301
1,643
214
Acworth, GA
Oct 17, 2017
#12
  • Oct 17, 2017
  • #12
They sell the friction modifier at the parts store too. Doesn't HAVE to come from Ford. If buying OEM is stuff is your game, I don't blame you though.

Kurt
 
Reactions: General karthief

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
10,570
203
polk county florida
Oct 17, 2017
#13
  • Oct 17, 2017
  • #13
I guess I have a relationship with my local ford dealer, have had bad experience with parts stores.
When your dealing with a 97 sd, with the body change for the f150 and not the sd always got wrong parts, f350 parts instead of sd (they didn't call it a f450 just f super duty)
 
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