Gear Oil for 105 series diffs (1 Viewer)

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Just wondering what people use for diff oil and transfer case oil. Is it standard for all models?

I have 105 series and just want to be sure I'm using the correct viscosity for front and rear diffs.

I think I should be ok for 80W-90 in the diffs and 75W-90 for transfer.

What does it mean with the temperature recommendations? They are weird. I take it below -18 is for snow areas, rarely (if ever) gets to 0 celcius where I live.

Page from the online downloadable Owners Manual /Specifications (not my cars).
Capture.JPG


Going to try and freshen up the lot of this with new oil / grease. Is it better to install new zerks to avoid injecting sand/contaminants ?

Going to use these:

A7889410-1.jpg


A9449198.jpg


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Purchased the grease already , since the previous owner used Auto MAsters who use only Valvoline products (lubrication/oil)

Is there a synthetic or semi-synthetic option for 100 series diff oils ?

Advice would be much appreciated. Cheers.
 
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either 80-90 or 75-90 will be fine for diffs and t-case. 75-90 is the easiest thing to get at the shop so that's what we use in everything and no issues. temp recommendation is for running in constant temps, if you don't get to 0 c stick with 75-90 itlll cover a more broad range of operating temps.

change the grease fittings of their broken or very clogged, no need otherwise.

there are plenty of syn and semi syn options but seeing that your in aus you would be better off asking someone more local as they will have better recommendations
 

abuck99

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Unless your living in Perisher Valley, It probably gets HOT AF where you are in Oz and depending on how you use your 105 thicker is better for hot harsh environments- 90wt better than 80/90, better than 75/90- you want GL5 rating, note - some folks have had issues with leaking axle seals and use of synthetic- If you're worried about econ- thinner but if you have lockers- better to run a little thicker. FWIW TJM Locker recommends Castrol SYN 80/140 in diff's with their lockers.
 
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Unless your living in Perisher Valley, It probably gets HOT AF where you are in Oz and depending on how you use your 105 thicker is better for hot harsh environments- 90wt better than 80/90, better than 75/90- you want GL5 rating, note - some folks have had issues with leaking axle seals and use of synthetic- If you're worried about econ- thinner but if you have lockers- better to run a little thicker. FWIW TJM Locker recommends Castrol SYN 80/140 in diff's with their lockers.
Yeah no lockers, I imagine the same goes for engine oil. Hotter temps and depending on what gear you're running / size tyres, suspension how hard the engine works the thicker the oil. I recently purchased 15W-40 oil for the engine and then finally understood that rating relevant to external temp. I'd argue those viscosity ratings are more relevant to USA outside temperatures. Here in Aust. it is on average a little hotter than American weather. Must be why this vehicle was running 20W-50. Lucky its just hit winter though so 15W-40 should be ok until summer rears its head again, then I might just go back to 20W-50 depending on whether I see any improvement on fuel economy. Only thing that would change my mind cos currently I think I could go a bit better

Anyway, back to gear oil. Thanks for the advice and information.

I will definitely reconsider the semi-synthetic as diff oil, no lockers in this vehicle but it does get a good work out in the sand every so often.

I've checked the zerkz and they have quite a thick layer of oil + dirt residue over them. I will try clean them up best I can, but wonder if some of this does get into those zerks over time? Not sure how big the hole is in those enoguh for stuff to penetrate?

Good info, cheers.
 
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I've checked the zerkz and they have quite a thick layer of oil + dirt residue over them. I will try clean them up best I can, but wonder if some of this does get into those zerks over time? Not sure how big the hole is in those enoguh for stuff to penetrate?

best guess very little to none, and what does get in there will be mixed grease and will eventually work its way out with minimal damage to the u-joint. i would be more worried about lack of maintenance from the po than the possibility of a few grains of san in a grease fitting.
 
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best guess very little to none, and what does get in there will be mixed grease and will eventually work its way out with minimal damage to the u-joint. i would be more worried about lack of maintenance from the po than the possibility of a few grains of san in a grease fitting.

The back slip yoke appears to be the worse maintained , thick black grease came out of that with minimal squeezes of the grease gun.

I pumped and pumped and pumped until this grease seemed predominantly blueish (colour of the new grease).

However, why would grease suddenly stop going past that point again ? There was grease coming out of the gun still , I pulled it off the zerk and squeezed some out. Seems as if it ceased up again, you could see the tube pushing out , but no grease was making it past again.

Should I keep pumping with a new tube of grease, perhaps the grease gun loses pressure when it reaches the end of the tube. Or is there crap in the slip yoke that needs to work its way out with more pumps of the gun.

Help/advice appreciated !
 
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you way overfilled the slip joint, that should only be getting a few pups every service, it sounds like you used most of a tube of grease so the joint will be hydro locked and not act as a slip joint. pull the grease fitting and compress the shaft to let some grease out.

and yes nothing will come out of the grease gun when your almost out of grease, youll never get all of it out of the tube
 
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you way overfilled the slip joint, that should only be getting a few pups every service, it sounds like you used most of a tube of grease so the joint will be hydro locked and not act as a slip joint. pull the grease fitting and compress the shaft to let some grease out.

and yes nothing will come out of the grease gun when your almost out of grease, youll never get all of it out of the tube
Yeah I will try help some out a bit. Take it for a drive , heat it up, try a new grease stick on it , maybe take zerk off , put a new one on. Give it a good bang with something non damaging. When I have time next. Might measure it today so in uture I know if its moving.
 
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Yeah I will try help some out a bit. Take it for a drive , heat it up, try a new grease stick on it , maybe take zerk off , put a new one on. Give it a good bang with something non damaging. When I have time next. Might measure it today so in uture I know if its moving.


take the grease out first before driving, the slip joint is there to take up drive line compression. if the joint is full and hydro locked yout t-cast and pinion in the rear will be taking all the load from drive line compression and they don't like it. if its that full the grease will start coming out as soon as the ffitting is removed
 
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take the grease out first before driving, the slip joint is there to take up drive line compression. if the joint is full and hydro locked yout t-cast and pinion in the rear will be taking all the load from drive line compression and they don't like it. if its that full the grease will start coming out as soon as the ffitting is removed
Not happy with it like that, however compared before and after and its not as bad as it seems really. I've been told that I can just unbolt one side of it , pop it out and then force it in again while pushing grease out with the zerk off. That sound like something that would help it back ?
 
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and yeah I chucked a bucket while pushing the zerk plug in with an old ballpoint. Stuff just started oozing out straight away and it appeared as if some stress was leaving the shaft (made weird sounds). But, no more coming out of either now. It only really clunks on changing from D to R and then back again. Drive goes well from first take off no sound.

Comparison of the before and now. Front
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back:

97931049_536442277040405_4773033525827862528_n.jpg
98599759_568500533682625_3808588328769421312_n.jpg


I obviously just need to push a both in a bit more. I don't have stands so can't exactly prop it up so I can turn the shaft while unbolting.

I have 2 jacks tho , the cars and a 2 tonne wheel in jack
 
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I've been told that I can just unbolt one side of it , pop it out and then force it in again while pushing grease out with the zerk off.

you can do that as well and if your up to it you can even disassemble the slip joint and clean it up. mark both sides of the shaft and pull the slip joint apart and get at it with some rags and brake clean. you can also use a little valve grinding compound to smooth out the joint, just make sure that you clean all of the compound off.
 
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its fairly normal to get some clunk from r-d or d-r as there is a lot of slop in the drive train between the t-case, drive flanges on the front, backlash in the rears, ect. slip joints look good, maybe a light sanding with a finer emery cloth to take down any ridge where the u-joint normally sits and any rust that may have build up from lack of grease.
 
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you can do that as well and if your up to it you can even disassemble the slip joint and clean it up. mark both sides of the shaft and pull the slip joint apart and get at it with some rags and brake clean. you can also use a little valve grinding compound to smooth out the joint, just make sure that you clean all of the compound off.
yeah still gotta get at all the bolts (some jack stands probably)
 
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its fairly normal to get some clunk from r-d or d-r as there is a lot of slop in the drive train between the t-case, drive flanges on the front, backlash in the rears, ect. slip joints look good, maybe a light sanding with a finer emery cloth to take down any ridge where the u-joint normally sits and any rust that may have build up from lack of grease.

Yeah this part here even appears to be doing its job still and sliding. Not sure whats going on, cos I pulled this zerk off this one (front) and no grease leaked out. Sat there in the housing.
1589718561909.png
 
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not having grease pour out is just fine, its probably filled the correct amount so no need to add to the joint. drive and check at a later date there should be a little grease on the slip joint from the joint cycling in and out, no grease on the joint add 5-8 pumps
 
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not having grease pour out is just fine, its probably filled the correct amount so no need to add to the joint. drive and check at a later date there should be a little grease on the slip joint from the joint cycling in and out, no grease on the joint add 5-8 pumps
Will do, cheers.
 

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