Getting ready to change my front dif fluid on a 04 Rubicon. I have seen a couple of videos saying to use break cleaner to clean the dif before replacing the cover and filling. Is his good to go on a Rubicon locker? Advice appreciated!
Should I use brake cleaner for front differential maintenance?
- Thread starter Bud125
- Start date
Meeh, pull the cover, don't directly spray brake clean on the locker hose if it makes ya nervous (I sure have without ill effects thus far) and look over everything inside for problems ya haven't heard yet... Cheaper to fix before something blows up... Its an every 12k max duty with a TJ 
... Oh and pull the plug too, so you can clean the magnet
... Oh and pull the plug too, so you can clean the magnet
Last edited:
OP
Thanks for the replies. Yes I would like to take a look inside since this is a new to me TJ. I also have an aftermarket dif cover that I may install. I think I will not use any break cleaner just drain, look, replace.
Pull cover. Be sure all gasket material is scraped off housing and cover. Use a rag or paper towel to wipe out bottom of diff. Inspect rag for any metal shavings or bits. If it looks good then new gasket and reinstall cover. Fill.
If you find metal in the bottom of the diff then now is the time to get ready for a rebuild.
If you find metal in the bottom of the diff then now is the time to get ready for a rebuild.
OP
I'd use brake cleaner. It will take any oil off the gears and you can inspect/see them better without a coating of oil all over them. Plus, brake kleen dries quickly. Just soak up everything with a few paper towels.
The brake cleaner is mainly for the mating surfaces. Clean them well, RTV gasket maker or new gasket. Should be good to go. You would likely know if something was wrong. Use towels to clean oil out of bottom as others suggested. Brake cleaner should be absolutely fine though.
Aftermarket diff covers can have clearance issues and change the oil fill level. Check the clearance by cycling the suspension and always follow manufacturers suggested fill capacity.
TJ2
TJ Expert
I use brake cleaner a lot to all my rigs. It is alcohol based and it dries so quickly that you don't even know you used it. The oil/gunk sediments will settle in the bottom and it is all cast / forged metal catch basin.
Keep in mind, the TJs are built simple with old conventional parts like the farm tractors in the '60s.
Keep in mind, the TJs are built simple with old conventional parts like the farm tractors in the '60s.
Do only the Rubicon D44s have the drain plug on the bottom? I have a rear Dana 44 from a '98 TJ and there is not a drain plug on the bottom only the fill plug on the cover.
Some formulations of brake cleaner can definitely be fatal to rubber/neoprene. The real danger is that the hose can look fine afterward so you put the cover back on but start cracking and failing weeks later.
I hose anything I want cleaned up with brakleen.
Only time I don’t use it is if I’m going to weld something.
Only time I don’t use it is if I’m going to weld something.
TJ2
TJ Expert
My brake caliper assembly brake-cylinder boot is thin rubber material, it gets soaked a lot with brake cleaners. I have never seen it gets brittle in years.
There's a lot of good information on brake cleaners at https://en.wikipedia.org/wiki/Brake_cleaner including a warning that it can harm, often fatally, rubber and some plastics.
the factory service manual specifically states to flush it out with clean gear or motor oil, and NOT to use gasoline or kerosene. It doesn't specifically mention brake cleaner, but my hunch is that it's more similar to the stuff they tell me NOT to use than it is to oil. In a conventional diff without any plastic or rubber hoses I have no idea what harm it could do, but I'm not a chemist and it seems like an odd thing to put in the manual if there wasn't a reason for it.
I don't buy the argument that it doesn't matter because it evaporates so quickly, because while it does on an otherwise dry surface, it likely gasses off much more slowly once it's been mixed with residual gear oil. My reasoning for this is that when I have mixed it with gear oil, I can still smell brake cleaner in it hours later.
That said, it's used to clean out probably hundreds of axles per day all over the country and I'm unaware of any failures or damage attributed to brake cleaner.
I don't buy the argument that it doesn't matter because it evaporates so quickly, because while it does on an otherwise dry surface, it likely gasses off much more slowly once it's been mixed with residual gear oil. My reasoning for this is that when I have mixed it with gear oil, I can still smell brake cleaner in it hours later.
That said, it's used to clean out probably hundreds of axles per day all over the country and I'm unaware of any failures or damage attributed to brake cleaner.
I opened both mine and cleaned w/brake cleaner an switched on the lockers to make sure every thing looked good cause my front light always flashes,,,,but they both work perfect, the air pump never turns back on after the lock......turns out it the ign.when I jiggle the key the light goes solid....