post your latest differential fluid change

Mom's 2005 Jeep Grand Cherokee.
Out: Valvoline synthetic 75w140
In: RP synthetic 75w140
reason: Some store was selling the RP at an insanely low price.
 
Jeep Cherokee '08 2wd 3.7L

Out- M1 75-140.
In- amsoil x-110 SG

notes: avg mpg up .4-.6 mpg average over 2 months time. see bottom---
notes 2: the mobil 1 only had 10,000 miles on it and came out darker than the oem fill with 30,000 miles on it.

friend's 05 tahoe
out- 80-90w front and rear, oem fill
in- 80-90w M1 syn

out- oem T-case fluid
in- oem T-case fluid (GM's blue, special magic mix-- was tempted to use ATF+4)

notes: old stuff was dark and thin, looked pretty bad.
notes2: mentioned seeing slight increase in MPG and quieter hwy ride.
notes3: the tcase made a racket before, MUCH quieter now.

bottom-- I changed it early since new All Terrains had so much rolling resistance that the trans was seldom going in to lockup... going from oem 245-65 to 245-70 I saw a 2-3mpg drop. i see no reason to run a 140 in the diff, opted for the 110 instead, hoping to reduce driveline losses. there was a slight butt-dyno difference, but the real kicker is that it's just enuf that trans now goes into lockup again. still touchy, but it was just enough to make a difference. YES, I'm running a thinner spec lube. But if this unit dies from using 110 instead of 140, then there are other problems that were going to kill it anyway.
 
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4 portal boxes 700ml each
2 diffs 2.5L each
Delvac Synthetic Gear Oil 75W90.
Portals run at 130-140F. after all day at 85-90kph at 75F.
Diffs run about 170-180F.


Charlie
 
~2 qts. of Red Line 75W-140 with 4 oz. of Ford XL-3 friction modifier, and one 8 oz. bottle of the Lube Guard diff additive.

I am going to try the Amsoil Severe Gear 75w-110, or 140 next change.
wink.gif
 
1999 F250 Super Duty. 145k miles. RP Max Gear drained, replaced with 3.5 quarts of Valvoline SynPower 75w140. No other additives. New Fel-Pro pumpkin gasket installed. Rear end still looks good inside at this mileage, and no issues to speak of.
 
Drained the rear diff in the Wife's 09 Forester...30k miles.

Out - factory fill (very little debris on magnet, drained clear)
In - 75w90 Amsoil SVG

I intended to also drain and fill the front differential, but didn't realize they used a #70 Torx on it...so it will need to wait.

I changed the truck a few months ago:

Out - RP 85w140 (over 100k miles on it, no debris on magnets)
In - Schaeffer 75w140 and two 4oz bottles of Mopar LSD modifier.
 
2008 Dodge Ram 1500
38,000 mi

Rear
Out-factory fill
In-Mobil 1 75W-140

Front
Out-factory fill
In-Mobil 1 75w90
 
1989 Volvo 744T

Out: Factory fill (Probably) 80w-90

In:
Valvoline Synpower 75w90

The magnet probably had a 1/4" of fine filings on it. The old fluid also smelled absolutely disgusting, I had to get a fan under the car so I could breathe without getting sick. Washed out the diff with brake cleaner. The fluid was a dark brown, and definitely needed changing.
 
Ive owned my 1981 isuzu pup 4x4 w/ 4spd trans.
99% hwy driver 99% under 55 mph. 155K

Never submersed diffs under water (like through streams etc)
The diffs have a vent that can let water in Im told)
I checked the rear diff with my pinky and couldnt get any oil(goil) on my finger.(2nd knuckle)
i forgot to measure what was actually in it as I drained it out.

The only reason I checked it was I developed a very slight whine on very minimal throttle depression at around 50 mph. Conversely,It would disappear with light release of the throttle
I suspected wear on the pinion contact,but not sure.
I flushed out with diesel(made some sense to me to clean out best I could before refilling)
I will let it churn for a few hundred miles or so then replace with. Well thats where Im undecided. What weight oil and is syn worth it as a new replacement?
Sounds like new topic material,think I will.
 
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1990 F150 3.55 Non-Limited Slip Differential

Out: Supertech Synthetic Blend 75w-90
In: Amsoil Severe Gear 75w-90

I can't say enough good things about the Amsoil Severe Gear to be perfectly honest. You'd think I was hallucinating if I actually mentioned what I've observed since changing it to Amsoil. Yes, it is just that good. I wish I would've changed it to Amsoil when I first bought the truck. I figured the ST gear oil was good to flush and prep the differential before going to some big boy stuff.
 
1997 Toyota 4Runner SR5, 4WD

Rear Diff
Front Diff
Transfer Case

All Mobil 1, 75W-90, 5 Quarts in total used.

I have one quart of a heavier Mobil 1, 75W-140 on hand for any top offs.
 
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I am going to try the Amsoil SRN (Severe Gear 190 Racing) and SVO (Severe Gear 75W-140) in a 50/50 mix tomorrow to try and quiet down the decel only whine/scream of my 10 bolt.

If that does not work, I might drain out a pint, and add 1 pint of the SRT (Severe Gear 250 Racing).

I am also going to add the absolute MINIMUM amount of limited slip friction modifier possible this time around.
 
01 Durango. ST 75W-90 semi-syn. Front and rear diff. Vacced out old and added the new. 10k miles and very satisfied.
 
00 Durango 4.7L 4X4

Havent done the front diff in bit and its overdue

Rear
out: Mopar 75w-90
in: Castrol Syntec 75w-90
 
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