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Differential Oil Recommendations
- Thread starter hmsevans
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Bob_Spidell
Yoda
Offline
I use Redline 75W-90 in my (3.54) diff. Good stuff if you can keep in in :wink:
tahoe healey
Yoda
Offline
Haploid (spell)is what the books say for the differential.
Automotive Products: Two-Three Wheelers
Gulf EP Gear Oil 80/90/140
High Quality Gear / Transmission lubricant for Extreme Pressure conditions.
Excellent oxidation stability and protection against rust, corrosion & foaming.
Suitable for Manual transmissions, spiral bevel and hypoid gears in moderate to heavy duty service.
Recommended for use in cars, trucks, buses, construction equipment, steering boxes and oil lubricated universal gear joints.
Exceeds API GL-4, US MIL-L-2105, 1118 and UK Defence CS3000 performance level.
Gulf EP Gear Oil 80/90/140
High Quality Gear / Transmission lubricant for Extreme Pressure conditions.
Excellent oxidation stability and protection against rust, corrosion & foaming.
Suitable for Manual transmissions, spiral bevel and hypoid gears in moderate to heavy duty service.
Recommended for use in cars, trucks, buses, construction equipment, steering boxes and oil lubricated universal gear joints.
Exceeds API GL-4, US MIL-L-2105, 1118 and UK Defence CS3000 performance level.
Bob_Spidell
Yoda
Offline
Redline makes both 75W-140 and 80W-140 gear oils (the latter is only recommended for trucks). They do note the heavier oils are a slight bit less efficient, resulting in lower mileage.
https://www.redlineoil.com/products_gearl...mp;categoryID=6
-- or --
https://tinyurl.com/cnrqjr
I'd stick with 75W-90; the first time I put it in it didn't leak but I pulled the diff a second time and now I'm getting a small drip, so it's at least partly in the installation. I ran Redline 75W-90 on a new (3.54) ring and pinion and both the ring and pinion showed hardly any wear after approx. 15K miles (the machine marks were still visible on the wear surfaces). My main concern is the hub bearings, which are of course lubricated by the diff oil. I've had to replace several of those and would prefer not to have to do that many more times. I think the synthetic would be at least as good as mineral gear oil for them.
Note I don't work for Redline or sell their products; I tried MT-90 in my BJ8's gearbox and was surprised by smoother shifting and better O/D response when hot, so I put their gear oil in the diff. It seemed to me there was less brass shake in the transmission oil when I changed it out. FWIW, I don't buy the 'let the crud fall to the bottom' theory--the suspended (mostly brass) particles are so fine they aren't gritty at all and they are too small to plug any passages (I used 20W-50 motor oil before and never had any problem--I've put over 100K miles on my drive train). Any chunks large enough to plug a passage will probably do so whether you run mineral or synthetic--assuming the screen doesn't catch them--and I don't think having a bunch of sludge in the gearbox is necessarily a good thing. YMMV.
https://www.redlineoil.com/products_gearl...mp;categoryID=6
-- or --
https://tinyurl.com/cnrqjr
I'd stick with 75W-90; the first time I put it in it didn't leak but I pulled the diff a second time and now I'm getting a small drip, so it's at least partly in the installation. I ran Redline 75W-90 on a new (3.54) ring and pinion and both the ring and pinion showed hardly any wear after approx. 15K miles (the machine marks were still visible on the wear surfaces). My main concern is the hub bearings, which are of course lubricated by the diff oil. I've had to replace several of those and would prefer not to have to do that many more times. I think the synthetic would be at least as good as mineral gear oil for them.
Note I don't work for Redline or sell their products; I tried MT-90 in my BJ8's gearbox and was surprised by smoother shifting and better O/D response when hot, so I put their gear oil in the diff. It seemed to me there was less brass shake in the transmission oil when I changed it out. FWIW, I don't buy the 'let the crud fall to the bottom' theory--the suspended (mostly brass) particles are so fine they aren't gritty at all and they are too small to plug any passages (I used 20W-50 motor oil before and never had any problem--I've put over 100K miles on my drive train). Any chunks large enough to plug a passage will probably do so whether you run mineral or synthetic--assuming the screen doesn't catch them--and I don't think having a bunch of sludge in the gearbox is necessarily a good thing. YMMV.
dougie
Luke Skywalker
Offline
The only oils I use in my race Healey are Redline and have been very satisfied with their performance under race conditions. I have also started using them in my street Healey , MT-90 in the BJ8 transmission and overdrive with great results.
As well as the benefits described by Bob, I think it runs much more quiet.
Dougie
As well as the benefits described by Bob, I think it runs much more quiet.
Dougie
AUSMHLY
Yoda
Offline
My garage floor shows every so often I have a drop of oil from the differential/rear end. Not sure how much oil I've lost over the years and thought this would be a good time to look into either adding oil or draining it and replacing.
The Austin Healey Drivers Handbook says every 6,000 miles, check the oil level and replenish if necessary.
When should the rear axle oil be drained and refilled?
Handbook says, "Use only Hypoid oil in the rear axle".
Handbook recommended Lubricants: Duckham's Hypoid 90, Castrol Hypoy, Sternol Ambroleum E.P. 90, Mobilube G.X.90, Esso Gear Oil G.P. 90, Filtrate Hypoid Gear 90, BP gear oil S.A.E. 90 E.P. , Shell Spirax 90 E.p.
Research found Healey Surgeons recommends, "Use 80W/90 EP Gear Oil". They don't mention a brand.
Moss sells, Dynolite SAE 90 GL4 Gear Oil.
This tread:
Hypoid 90/140, API GL5 or better.
Gulf EP Gear Oil 80/90/140
To recap.
When to do a fluid change?
What brand/weight of GL4 oil do most people use?
Seems a single grade 90 is recommended by the Austin Healey Handbook. (what's the advantage of multi-grade?)
Thank you.
The Austin Healey Drivers Handbook says every 6,000 miles, check the oil level and replenish if necessary.
When should the rear axle oil be drained and refilled?
Handbook says, "Use only Hypoid oil in the rear axle".
Handbook recommended Lubricants: Duckham's Hypoid 90, Castrol Hypoy, Sternol Ambroleum E.P. 90, Mobilube G.X.90, Esso Gear Oil G.P. 90, Filtrate Hypoid Gear 90, BP gear oil S.A.E. 90 E.P. , Shell Spirax 90 E.p.
Research found Healey Surgeons recommends, "Use 80W/90 EP Gear Oil". They don't mention a brand.
Moss sells, Dynolite SAE 90 GL4 Gear Oil.
This tread:
Hypoid 90/140, API GL5 or better.
Gulf EP Gear Oil 80/90/140
To recap.
When to do a fluid change?
What brand/weight of GL4 oil do most people use?
Seems a single grade 90 is recommended by the Austin Healey Handbook. (what's the advantage of multi-grade?)
Thank you.
Bob_Spidell
Yoda
Offline
I use Redline 75W-140 in my BJ8 to damp a little diff whine, and 75W-90 in the BN2. I'm comfortable leaving it for 10yrs/50K miles or a bearing/seal change, whatever comes first.
Offline
Hey Roger,
This is not what you asked, but I will volunteer it anyway. After all, that seems to happen a lot here!
you started by mentioning that every now and then you get a differential oil drip on the floor. I had the same thing and was on a mission for a while to stop it. I tried lots of things from sealants to new plugs and etc. I finally tried the yellow pipe thread Teflon tape - NOT the white stuff - white did not work for me. The yellow worked! I have not had a single drop on the differential or the floor since I installed the yellow tape. Just thought I would share.
Lin
This is not what you asked, but I will volunteer it anyway. After all, that seems to happen a lot here!
you started by mentioning that every now and then you get a differential oil drip on the floor. I had the same thing and was on a mission for a while to stop it. I tried lots of things from sealants to new plugs and etc. I finally tried the yellow pipe thread Teflon tape - NOT the white stuff - white did not work for me. The yellow worked! I have not had a single drop on the differential or the floor since I installed the yellow tape. Just thought I would share.
Lin
AUSMHLY
Yoda
Offline
Hey Lin,
I do appreciate that information. I am Leary of using any type of sealing tape around threads...will some pieces tear off and get into the oil?
I was thinking of using Hylomar Advanced Formulation gasket and jointing compound (blue) (I think it's the same as Hylomar Universal blue) around the outside edges of the plug. I've used that around the exterior of the bolt heads at the steering box and that solved that leaking issue.
The yellow pipe thread is a cleaner solution.
I do appreciate that information. I am Leary of using any type of sealing tape around threads...will some pieces tear off and get into the oil?
I was thinking of using Hylomar Advanced Formulation gasket and jointing compound (blue) (I think it's the same as Hylomar Universal blue) around the outside edges of the plug. I've used that around the exterior of the bolt heads at the steering box and that solved that leaking issue.
The yellow pipe thread is a cleaner solution.
Bob_Spidell
Yoda
Offline
Sealing tape--white or yellow (yellow is for gas fittings)--is/should be made of Teflon. The shear forces in a diff and the pressure in the bearings will grind the tape into oblivion, giving you an extremely dilute Slick 50 (so it's not likely to be a problem in a diff). I'd be leery using it where small passages could be plugged, though, like brakes.
I use white/Teflon pipe sealant on the plug--it's a pipe thread, after all--and it's worked well for me. Look closely to make sure the diff hasn't been cracked by a ham-fisted mechanic trying to stop a drip.
I use white/Teflon pipe sealant on the plug--it's a pipe thread, after all--and it's worked well for me. Look closely to make sure the diff hasn't been cracked by a ham-fisted mechanic trying to stop a drip.
AUSMHLY
Yoda
Offline
Bob, Redline says for limited slip differentials. Healey's aren't limited slip are they? It doesn't say recommended for GL-4. Is that ok?
This is from Redlines website:
[h=1]75W140 GL-5 GEAR OIL[/h]
- Popular for cars and light trucks like Ford Mustang and F-150, Toyota Tundra and Sequoia, Jeep Cherokee and Dodge Ram
- Contains additional friction modifiers for suitability with clutch-type limited slip differentials - for most LSDs, no additional friction modifiers are required
- This product is not designed for use in most manual transmissions or transaxles, since the extreme slipperiness may cause synchronizer mesh issues that lead to shifting problems
- Recommended for API GL-5, GL-6, MT-1, MIL-L-2105E and SAE J2360
Offline
GL-5 oil is more resistant to shearing forces.
I use Amsoil Severe Gear EP 75/140 on all my cars.
I use Amsoil Severe Gear EP 75/140 on all my cars.
AUSMHLY
Yoda
Offline
Handbook says, "Use only Hypoid oil in the rear axle".
Handbook recommended Lubricants: Duckham's Hypoid 90, Castrol Hypoy, Sternol Ambroleum E.P. 90, Mobilube G.X.90, Esso Gear Oil G.P. 90, Filtrate Hypoid Gear 90, BP gear oil S.A.E. 90 E.P. , Shell Spirax 90 E.p.
Moss sells, Dynolite SAE 90 GL4 Gear Oil.
This seems to be the closes I can find to a single 90W.
Are the GL-5 Multi-weight oils better?
Are any of the multi-weight oils referenced prior, synthetic? Is Synthetic different from a Hypoid oil?
Handbook recommended Lubricants: Duckham's Hypoid 90, Castrol Hypoy, Sternol Ambroleum E.P. 90, Mobilube G.X.90, Esso Gear Oil G.P. 90, Filtrate Hypoid Gear 90, BP gear oil S.A.E. 90 E.P. , Shell Spirax 90 E.p.
Moss sells, Dynolite SAE 90 GL4 Gear Oil.
This seems to be the closes I can find to a single 90W.
Are the GL-5 Multi-weight oils better?
Are any of the multi-weight oils referenced prior, synthetic? Is Synthetic different from a Hypoid oil?