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Another transmission fluid question

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AUSMHLY

AUSMHLY

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I asked my mechanic what he recommends for transmission fluid. Here's his reply.

As for the oil, 20-50 Castrol is fine as far as I'm concerned and don't see the point of synthetic. It's more important that it get changed as often as the engine oil (BJ8 gearbox's are more sensitive to degradation of the caged needles).

Is anyone using 20-50 Castrol? Happy with it, if so?
Anyone changing the oil as he recommends doing?

Roger
<span style="color: #3333FF"> </span>
 
Roger, I have been using Valvoline 30W non-detergent oil for years in my BJ8 gearbox and overdrive. I buy the theory that a non-detergent oil is desirable in the gearbox because you don't want the wear particles suspended in the oil and continuously circulating through the bearings as happens in a detergent oil. There is no filter to remove debris, so it's better to let it settle out to the bottom of the 'box between drives. I have also stuck several small magnets to the bottom of the gearbox to "coax" any magnetic debris to the bottom.
Last summer, after not being able to find my usual Valvoline, I used a cheap 30W non-detergent bought at Wal-Mart (Accel brand). I began having problems with the overdrive sticking on intermittently until I changed to Redline MTL synthetic (based on rave reviews from several people on the Healey e-mail list). The oil change fixed my overdrive problem and I still have Redline in my car; but my conclusion is that there was no noticeable improvement in shifting as compared with Valvoline 30W non-detergent, and the high cost of the Redline does not justify its continued use. I will change back to Valvoline when I change oil in the gearbox/overdrive again.
 
Regular 30 weight after finding the p/o had put 90 weight gear oil in it... ummmm what a smell!!!
 
I don'd believe you will find a 20-30 wt non-detergern. Wasn't there something about detergent and brass? Don't mess with the trans. Too expensive to rebuild. Multi grades are for hot/cold applications. Not needed here. Poor shifting from improper lubrication is where you get those metal flakes that are kept in suspension by the detergent. Those little metal flakes in suspension are what mess with the needle bearsing he is talking about.
Interesting that your machanic would suggest that. I have had MGs and Jags before and none used anything but non-detergent in the gear box. Is this guy familiar to LBCs? You've got too much invested in your beautiful Healey.
You going to San Diego?
 
I am in the process of having my transmission rebuilt. To qualify the guy who is rebuilding it, the guys who says 20-50 and change the oil, is.......a healey mechanic that works on Healey race cars. This mechanic is the guy my local Healey mechanic had rebuild his transmission.

Check this out. This guy is rebuilding my transmission as a favor for my mechanic. The requirement is that I do a hands on repair with him. It's great. I now get to learn all about how a transmission is built. We ordered the parts from Dennis Welch. They are in and we should finish the total rebuild this Saturday. He tells me, that we will put a long day in. For we will also install it back in the car and I'll be able to drive home. Sweeeet.

Speaking of sweet, you should see this guys garage. I may take some photos and post them here. Full of Healey's. Right now there is a red and white works car there. Two Lotus race cars, and about 6 other Healeys.

Got parts? One wall is just bins of parts. You'd think you were in OSH. You name it, he's got it. Engines, Tranys, old parts, rebuilt parts, broken parts, lol....mine.

Back to the question at hand. Why he recommends 20-50. We will talk in depth about that one. Seems from my reading and folks here say non detergent 30.

Cheers all,
Roger
 
There's alot of talk about using a single grade non detergent oil in our gearbox.

Today I opened up the Drivers Handbook and the Workshop Manual. Here's what it recommends: (for my climate)

Engine and Gearbox
All conditions down to 5c (41f)

BP..........Energol SAE 40 or Super Visco-Static 20W/50
Castro......Castrol XL
Duckham's...Q20/50
Esso........Esso Motor Oil 40/50, Esso 40, Esso Extra 20/40
Filtrate....Filtrate Heavy Filtrate 20W/50
Mobil.......Mobiloil AF, Mobiloil Special 20W/40
Shell.......Shell Super motor oil, S-100 40, S-100, Multigrade 20W/40, 20W/50
Sternol.....Sternol WW40, WW Multi-grade 20W/50

Now it makes since why all three of my Healey mechanics recommend Castrol 20W/50. These guys only work on British cars.

They recommend changing the gearbox oil too. And it makes sence. No matter what oil you use, detergent or non detergent, you will get some things that should be drained out. The cleaner the oil, the less chance something small (metal, brass)that may be floating around, will go where it should not.

Happy Healey motoring!
Roger
 
Hi Roger, The 20w-50 means that when the car gets to operating temp, then the oil transforms itself into 50w. When it is cold it is 20w.
I know you are probably going to follow his recommendation but straight 50w motor oil would work the same as the 20w-50 in your your transmission once your car is warmed up. If your o/drive is in good shape, either the 20w-50 or straight 50w should work fine. The MT90 is equivalent to 40w motor oil in viscosity. Your mechanic's mechanic is saying use 50w instead of 40w or 30w.
Keoke said he uses 60w in the summer and 50w in the winter for the last 20 years.
Have fun Saturday.
Ed
:hammer:
 
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