Diff oil change...........

[Banditsteve]

Hi All,
Just wondering if somebody can help me out with a couple of questions I have. In the next couple of weeks I am hoping to get my diff oils changed and was wondering which oils I need. In the workshop manual it says SAE 75W/140 Synthetic oil for both the front and rear axles. Is this correct? My confusion is because it lists a couple of axles and I am not sure which axles are in mine. I have a 2002 Jeep Cherokee (Liberty) 2.4 Petrol with a 5 speed manual gearbox. It mentions something about trac-lok but not sure whether mine has this so if somebody could enlighten me I would be very grateful. I am also assuming the diff cover has to come off the rear to drain it? Do I just use normal silicone sealant to re-seal it? Or RTV Silicone? And it also mentions friction modifiers? Do I need those or not? Is thera a copper sealing washer on the front axle drain bung or is it just a tapered thread?When I was a lad you just stuck EP80 or 90 in axles and that was that!! Why do people have to complicate stuff? Sorry for all the question but just don't want to get halfway through and realise I need something I don't have! Thanks in advance Guys. Steve

 

[kb0nly]

I'm working on this here myself. Just did the transfer case today before it got too hot outside, no garage to work in...

I'm going with 75W-140 in the front and rear, i do some towing and thats what they recommend for heavier use. But i think for any use your well off using that viscosity.

If you have trac-loc, aka a limited slip differential, then you need the friction modifier, if you don't then you can just put in plain fluid and your done. Some even stock a 75W-140 with friction modifier added. If you don't need it you don't have to put it in, but if you don't need it and do put it in you won't hurt anything anyway, its just protection you don't need.

Look on the rear axle, one end or the other should have a colored sticker wrapped around the axle tube, it will say Open-Case or Trac-Loc on there. Open case means a standard diff, and Trak-Loc is the limited slip that needs the friction modifier.

The front diff plugs just threaded into the housing, no washer, you need a bit of pipe dope or plumbers tape on the threads when you put them back in to seal up. Don't overtighten as its aluminum. Snug works! I also found the specs on here and its 110 Inch Pounds if you use a torque wrench, so thats like just snug to me, just a smidge over 9 ft lbs, so not very tight!

The rear you need some good permatex high temp silicone, i got some red that i'm going to use. Get some rags and some brake cleaner so you can clean everything good before reinstalling the cover. U probably know the drill, apply silicone, let dry for half hour, then bolt on cover. The rear cover bolts are 30 ft lbs of torque, tighten in a star pattern to avoid warping.

 

[Banditsteve]

No sticker......... Bugger!

Hey kbOnly, Thanks for the quick reply. Just been out and had a roll underneath but no stickers. Is there any other way of identifying the diff or is there another way of realising if it has trac-lok? Thanx. Steve

 

[kb0nly]

Other than pulling a build sheet from Chrysler or removing the rear cover no...

However... Just buy the gear lube with the modifier in it, i did because its all Napa had on the shelf in 75W-140, says limited slip on the bottle, its Valvoline brand synthetic. That was if you have it or not your good to go. I looked at a few other stores after buying this stuff at $13.99 a quart, thinking that maybe someone who sold it without the friction modifier would have it cheaper, and nope, still about the same price regardless.

Oh and get yourself a Lower Unit Pump, used for putting gear oil in a Marine engines lower gearcase. Looks like a hand soap bottle pump that screws right onto the bottle of gear lube, put the hose up into the fill hole, and pump it... Lot easier than any other way of doing it.

I just found out i have to go buy a new pump, but they are only like $8 here. Any marine store or such should have them. Even Wal-Mart carries them. Why a new one? The one i have doesn't seem to seal anymore inside the pump and won't push fluid, glad i decided to check it before draining the diffs this evening... LOL

 

[Mangate]

I filled both diffs with the Mopar 75W90 synthetic stuff (cost me about $7 a litre at the dealer). MS9763 is the mopar number. I don't do any towing. The bottles have the short nozzle so easy to fill the diff.

 

[moparman]

Hey kbOnly, Thanks for the quick reply. Just been out and had a roll underneath but no stickers. Is there any other way of identifying the diff or is there another way of realising if it has trac-lok? Thanx. Steve

Jack up the rear axle until both wheels are off the ground...

 

[kb0nly]

Jack up the rear axle until both wheels are off the ground...

Good point... Jack it up and spin the wheels...

 

[tjkj2002]

Jack up the rear axle until both wheels are off the ground...

Good point... Jack it up and spin the wheels...

That only works if the LSD is still in good working order.A fried LSD will act just like a open diff doing a spin test.

 

[RenegadeJay]

Anyone ever try the Amsoil gear lube? I was at a show recently and Amsoil was a vendor there and their products sounded really good. Just curious because I will eventually need to do this maintance.

 

[ptsb5a]

Anyone ever try the Amsoil gear lube? I was at a show recently and Amsoil was a vendor there and their products sounded really good. Just curious because I will eventually need to do this maintance.

Yeah, I ran Amsoil Severe Gear but didn't leave it in for any longer than the recommended change interval. So, I dropped a butt load of cash on gear oil that got swapped out after 20K kms (12.5K miles). Won't do that again.

A friend of mine is an Amsoil rep and sold me some for his cost. It was still expensive for the time it spent in the diffs.

 

[mikey1273]

I want to do this to mine soon too. does anyone recall the tools and sizes of wrenches and socked needed? I want to be sure I have every thing before I start.

 

[AlexKJ]

I want to do this to mine soon too. does anyone recall the tools and sizes of wrenches and socked needed? I want to be sure I have every thing before I start.

Front Differential Drain Hole, 8mm Allen, 15 lbs-ft
Front Differential Fill Hole, 3/8" Ratchet, 15 lbs-ft
Rear Differential Cover Bolts, 13mm hex socket, 30 lbs-ft

 

[RenegadeJay]

Yeah, I ran Amsoil Severe Gear but didn't leave it in for any longer than the recommended change interval. So, I dropped a butt load of cash on gear oil that got swapped out after 20K kms (12.5K miles). Won't do that again.

A friend of mine is an Amsoil rep and sold me some for his cost. It was still expensive for the time it spent in the diffs.

Thank you for your input. Something to think about.

 

[rockymountain]

I'm running the Amsoil Severe gear. I have 14K on it now. Before the lift and tires I was getting 17.9 MPG consistently all city driving. Winter 17 or 16.9 usually. EVIC usually said 18.6. Not sure if it has anything to do with it though. Maybe not.

edit: using the 75 140
http://www.amsoil.com/storefront/svo.aspx

 

[SurfGuitar141]

Somewhere along the line Jeep changed the spec's on gear oil for the diff's...
The book on my '05 indicated 80W-90 for the front, and 75W-90 for the rear, unless you tow, then 75W-140 for the rear. It still calls for the friction modifier if you have Trac-Loc.
I also indicates synthetic or equivalent, which tells me a good quality dino oil is just as good, and that's what I used when I did my diff's a couple weeks ago....(Mobile Delvac 75W-90)

 

[Banditsteve]

Thanx All,
Hoping to get my diff oils changed next weekend. Thanx for all your comments. And I will get some photos of my Jeep when I get round to cleaning it!

 

[auburn4193]

Can anyone tell me if I have the LSD?

Build Sheet:
*M5 Cloth High-Back Bucket Seats -L5 Taupe AHMP Convenience Group I AJPP Power Convenience Group APAS Monotone Paint A53P 2.4L Eng(ED1)/5Spd M/T Nv1500(DDK) BAZS 136 Amp Alternator BC2S 600 Amp Maintenance Free Battery BRES 4-Wheel Disc Brakes CF5S Rear 65/35 Folding Split Seat CGS Supplemental Side Air Bags CGUS Child Seat Anchor System-LATCH Ready CG1S Next Gen Multistage Front Air Bags** CKDP Floor Carpet CKNS Cargo Compartment Carpet CKTS Cargo Tie Down Loops CK3S Plastic Swing Gate Trim Panel CLEP Front & Rear Floor Mats CLHP Cargo Trim Panel w/Storage Net CSRS Passenger Assist Handles CSWS Driver Assist Handle CTLS Base Door Trim Panel CUFS Full Length Floor Console DBBC All Manual Transmissions DDK 5-Speed HD Manual Transmission DHNS Command-Trac Part Time 4WD System DJJS Dana 30/186MM Front Axle DMFS 4.10 Rear Axle Ratio DRAS Corporate 8.25 Rear Axle ED1 2.4L I4 DOHC 16V SMPI Engine GBBS Tinted Windshield Glass GCBS Front Door Tinted Glass GEG Deep Tint Sunscreen Glass GEKS Flipper Swing Gate Glass GFAS Rear Window Defroster GNAS Rear View Day/Night Mirror GNCP Sun Visors w/Illum Vanity Mirrors GT9P Power Mirrors, Fold-Away GVBC All Vehicles W/Power Mirrors GXMP Remote Keyless Entry HAAP Air Conditioning I57S Route 57 - CSX & NS, Ridgefield, NJ JAYS Instrument Cluster w/Tach JCBS 120 MPH Primary Speedometer JHAS Var Intermittent Windshield Wipers JHBS Rear Window Wiper/Washer JJBS Dual Note Electric Horns JJJS 12V Auxiliary Power Outlet JJMP Auxiliary 12-Volt Rear Power Outlet JPHP Speed Sensitive Power Locks JPYP Pwr Windows, Front 1-Touch Down KJSS STRIPE/BADGE/MOLDING/COLOR KLSS STRIPE/BADGE/MOLDING/COLOR KRSS STRIPE/BADGE/MOLDING/COLOR K3AS STRIPE/BADGE/MOLDING/COLOR LACP Illuminated Entry LCDP Map/Dome Reading Lamps LDBP Cargo Compartment Lamp LHDS Headlamp Off Time Delay LMAS Halogen Headlamps LPSS CHMSL Lamp MDAS Front License Plate Bracket MFKS Body Color Grille MLCS Gray Fascias MVCS Jeep Badge MWGP Roof Rack NAS 50 State Emissions NBVP Low Emission Vehicle (LEV) NF2S 18.5 Gallon Fuel Tank NHFS Power Steering Cooler PJC Light Khaki Metallic Clear Coat QJCS Light Khaki Metallic Clear Coat RAAC All Radio Equipped Vehicles RBK AM/FM Compact Disc Radio w/Chgr Ctrl RCGS 6 Speakers RDDS Fixed Long Mast Antenna SBAS Power Rack and Pinion Steering SCDS Luxury Steering Wheel SDAS Normal Duty Suspension SUAP Tilt Steering Column TBBS Full Size Spare Tire TBRS Outside Tire Carrier TMXS P215/75R16 BSW All Season Tires TZAP Goodyear Brand Tires WKBS Matching Spare Wheel WLZC All Aluminum Wheels WND 16X7.0 Cast Aluminum Wheels XGGS Grocery Bag Hooks XJFS Tethered Fuel Filler Cap XPFS Protective Coating and Remover YAAS Build To U.S. Mkt. Specifications ZCGP Spring - Left Front ZCUP Spring - Left Rear ZRFP Spring - Right Front ZRUP Spring - Right Rear Z5AP GVW/Payload Rating 5I4S Four Wheel Drive (4WD)/(4X4) 5I8S Left Hand Drive (LHD) 5YAS KJ-Vehicle Family 594S Vehicle Order Tracking 6USS U.S. Specifications Label

 

[AlexKJ]

In my build sheet, the Trac-Lock diff appears this way: "DSAS Anti-Spin Differential Rear Axle"... So I'm leaning to think you haven't...

 

[moparman]

Doesn't look like it. Another way to tell - rainy road, 2WD, 1st gear, rev it up and dump the clutch with the wheels turned. If you do a 180, you have it. That is if the 2.4 can break the wheels loose. (If it can't, another sign of limited slip.) Don't call me if you hit anything or break something. I am partially joking, if I owned that thing, I would know by now. Just by it's behavior in loose traction situations.

Of course if it's a blown LSD, the tag on the plate or taking the plate off is the only way.

Once a drag racer, always a drag racer.