Front/rear differential fluid changed 3k miles ago, now mechanic says I need it changed again!

pX

Golden Member
Feb 3, 2000
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I have a 1998 Jeep Cherokee (LE, 4WD).
In June I had my oil changed here in Oregon (at a place called "Oil Can Henrys", a local(?) chain). At that time they said my front/rear diff fluid needed changed, they showed it to me on a little slip of paper and it was very dark, nearly black. I paid to get it changed ($100+) and went on my way.

3000 or so miles later I went back for another oil change and they said I needed to get front/rear diff fluid change again. The front diff fluid looked black and they said it had "shavings" in it. I thought I only need to change this stuff every 60k miles?! I told them that, and they checked their records and saw they had changed it before and sort of just said "weird" and didn't press me to get it changed.

Did I get ripped off (maybe they never changed it in the first place)? Is there some sort of mechanical problem that could make the fluid like this? I though the front diff was only used when I had it in 4WD, right? I haven't had it in 4WD in almost a year.

Any ideas/advice?
 

Greenman

Lifer
Oct 15, 1999
20,372
5,117
136
My guess ie they never changed it the first time, or the sample they show you isn't from your car.
 

OrganizedChaos

Diamond Member
Apr 21, 2002
4,525
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i've got a 97 and beleive it or not the manual says to change every 12k. i think its rediculous, diff fluid should be a 60k or 100k item. that being said though our rear axle, the DANA 35C is an absolute piece of junk. the dealer wants $1200 to fix mine(whines badly) and they weren't even sure whats wrong with it they said "probably the pinion bearings". i'm going to wait until next summer and if its still moves i'll buy new bearings, shims, seals, and maybe even a new carrier. front axle a DANA 30 isn't much better, i think its undersized for the vehicle. gear oil isn't expensive it should cost you $15 at the most to do the front and back yourself.
 

FelixDeCat

Lifer
Aug 4, 2000
29,172
2,036
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Ive changed mine on several cars because its relatively easy to do. The synthetic gear oil is about $10 per axle. Then youll need a cheap pump to put it in.

If they did it right the first time, the shavings would have fell out with the first oil change. BTW, unless you have a vehicle with more than 100k miles dont expect to see shavings. Most newer cars use synthetics, which inhibit oil breakdown and thus shavings from weak lubrication.

So if they did it right the first time, theres no "shavings this time" garbage. Tell them to go to hell and that your next stop will be your local television station if they dont stop that sh*t. Unless you watched them do it, more than likely they didnt even change it the first time and pulled some stock "black oil" to fool you. Its as old as the hills.

You can check it yourself. Put the car on level ground, get a socket wrench and remove the filler plug (all differentials have a fill plug and a drain plug). The oil level should be right up to brim of the fill plug. You should be able to touch the fluid and check the level yourself. If its black it was never changed to begin with. You can also have the dealer do this, but they will probably charge you a basic diagnostic fee for labor.
 

CTweak

Senior member
Jun 6, 2000
451
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They're ripping you off ... which is very common for places like this (Jiffy Lubes, etc). They always try and upsell add'l services, and many times the add'l services they sell are not even performed. I've seen several 'investigative' reports on news shows where they sting these places, and well over half of the quick lube places were cheating in various manners.
 

thehstrybean

Diamond Member
Oct 25, 2004
5,729
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Jeeps have sh!tty differntials and axles (unless you have one from before '90, then they put the Dana 40 in the inline sixes)....That's why I loved my '88...great gear box, and it had the better 4WD, hell of a lot better than my 01...That said, do your maintence yourself. It's easy. I changed my oil today in 10 minutes (only that wrong cause my oil pan screw was a pain in the a$$).