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How often should you change the rear rear axle oil

bob hughes

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I have had my car since 2002, I have checked and topped up the rear axle oil on several occasions, but I have never changed it. Having completed an oil change to the engine and gear box, the thought occurred to me that at some point I should possibly change the oil in the back axle. I went on a search through the Hand Book and the Workshop Manual and unless I have missed something, I could not find anything definitive.

Any Ideas?

:cheers:

Bob
 
Change it every 15 years or 15,000 miles..
 
A few years ago I went to change the Spitfires rear end oil only to find no drain plug. I don't think anyone I have talked to has any definitive answer to the question if the owners manual does not.
My feeling is topping off is probably all that's needed. The rear end is not seeing the byproducts of combustion the engine sees.
 
The rear end is not seeing the byproducts of combustion the engine sees.

All true, but having changed the gear box oil, there is a definite breaking down of viscosity with time and use, though the oil was clean as a whistle. Using Michael's suggestion, I had better consider changing because 15 years is now up and I passed 6,000 yonks ago. :glee:

:cheers:

Bob
 
Did you know what was in the axle when you topped it up? If you didn't, you might have mixed viscosities, which isn't a good thing.

Since you've never changed it, it would be a good idea to do so. Modern cars only recommend a change every 100-150K miles, and they make it difficult as the manufacturers don't put a drain plug in the diff housing. Put fresh oil in--I like synthetics here--and never worry about it again.
 
Bob--

Though my first response was said tongue in cheek I do think that diffs and transmissions often deserve better lubricant care than they get, and if anyone thinks these do not need draining/refilling, remove the drain plug, collect and examine the oils under bright sunlight and you will see a rainbow of metallic particles. Though shedding of fine metal is normal the point is that wear does take place and getting this stuff out of the equation can only add life to your gearbox or rear-end.

On my Healey, which currently sees no more than 5-6K miles per year, I still change both transmission and diff oils (Redline MTL and MobilOne synthetics) at least annually. And I change transmission and differential lubricants on my race cars every other race weekend as they see extreme use and the consequences of damaging either is costly both in terms of replacement and money/time lost to a DNF.
 
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... On my Healey, which currently sees no more than 5-6K miles per year, I still change both transmission and diff oils (Redline MTL and MobilOne synthetics) at least annually. And I change transmission and differential lubricants on my race cars every other session as they see extreme use and the consequences of damaging either is costly both in terms of replacement and money/time lost to a DNF.

Can't go wrong with that schedule, but I've generally changed my gearbox oil every 15-20K miles and the diff oil every 40-50K and never had any problems (IIRC, Norman Nock said to change gearbox fluid at 15K miles, and he was 'old school'). By 'never worry about it again' I presumed typical LBC owners don't put more than a couple thousand miles a year on their cars, so 20 years or so (how many of us gonna last that long?). My Mustang's scheduled diff oil change is at 150K miles, so the manufacturers think they aren't needed all that often (and it's a revenue stream for the dealers). The Mustang has a live axle and uses diff fluid to lubricate the rear bearings, just like a Healey.
 
Hi Bob,

Rear end gear oil should be changed whenever you change a part in the rear or axels (seals or components). Other then those events, I would expect the gear oil or synthetics to be just fine. Although changing the oil in the rear will not heart, since there is no source for continuous contamination as with the engine, I see no reason the rear oil would deteriorate and loose its lubricity. However, regular checking is critical to make sure the oil is up to level.

Keep in mind that the Mustang's schedule of 150K miles is, on a Healey, tantamount to never change.

Ray(64BJ8P1)
 
Hi Bob,

Rear end gear oil should be changed whenever you change a part in the rear or axels (seals or components). Other then those events, I would expect the gear oil or synthetics to be just fine. Although changing the oil in the rear will not heart, since there is no source for continuous contamination as with the engine, I see no reason the rear oil would deteriorate and loose its lubricity. However, regular checking is critical to make sure the oil is up to level.

Keep in mind that the Mustang's schedule of 150K miles is, on a Healey, tantamount to never change.

Ray(64BJ8P1)

Agree on all points, Ray (that's why I said 'never worry about it again'). But, if you have to dump the fluid, might as well put fresh in.

Side note: Looks like I'll be pulling the gearbox/OD on my BJ8, and draining the fluid. Since I just put almost 4qts of Redline's finest in--that's about $80--I'm debating trying to filter and save the fluid, and put it back in. Otherwise, a massive waste.
 
Side note: Looks like I'll be pulling the gearbox/OD on my BJ8, and draining the fluid. Since I just put almost 4qts of Redline's finest in--that's about $80--I'm debating trying to filter and save the fluid, and put it back in. Otherwise, a massive waste.

I have always tried to find an approach that allows for the least expensive highest quality solution to any Healey issue I encounter so, in this case, I would seriously consider filtering the fluid for re-use. That is, unless I had a failure that could have expelled a massive amount of small bits into the fluid...or even the potential of that happening. If I was concerned the fluid was compromised beyond filtration in any way, then spending the additional $80 is a cheap price for piece of mind.

Ray(64BJ8P1)
 
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