MGB Gearbox and Diff- oil types and change

This video addresses which oils to use and what not for the MGB gearbox and differential

[@davidgibson5756]

Nice description of the work. I always remove the fill plug first, just in case there is a problem with the threads. It also lets the oil drain easier.

[@D3Sshooter]

Great tip!

[@austinblanch1715]

I have always used mono grade oil 30w...used in Bridge & Stratton motor's...due to overdrive.

[@D3Sshooter]

I see\

[@dinot71]

In case it wasn't mentioned in another comment you never ever do the drain plug first you always do the fill plug first and then the drain plug second.

[@D3Sshooter]

yes

[@hankpb1]

I read it's 6 pints to fill mgb gearbox?

[@GOAT86STUDIO]

Nice job 👍

[@D3Sshooter]

Thanks 👍

[@phillippearce9680]

👍

[@richardkleihorst1304]

@steve: best to always remove the filler plug first, before letting out the oil. You'll never know. For the rear axle: is the GL4 oil suitable for hypoid axles?

[@D3Sshooter]

Indeed, and yes as long as you use the right density (SAE)

[@General813]

Hi Steve, nice video i've swapped out the gear and differential screw and now i use two with strong magnet (us made)...It's unbelievable what they fish out. With magnet is a good protection like a little filter and you have control over wear. Nice work Steve 😀

[@D3Sshooter]

That is indeed a good method to attrack metal particles,,,

[@cyoung4290]

Only thing I might add is to make sure you can get the fill plug out before you drain the oil … you sure don’t want to drain all the old oil then find out the fill plug is stripped or seized!

[@m.b.smoshitoa8325]

Steve there's something I don't understand. You said 20 w50 and 75w90 vescosity are the same. How so. I am lost shem😳 Your greatest follower MBS Moshitoa south Africa

[@D3Sshooter]

That is because they are using different methods to measure but the viscosity is the same,,, Its like pounds and kilograms,,,,

[@m.b.smoshitoa8325]

@@D3Sshooter but Steve if that is the case then why don't they use different thing like pounds and kilogrammes not W something which is the same. That confuses shem

[@mikes4408]

Have a 67 MGB and the 3 syncro trans, has the filler plug under the center hump carpet with a dip stick. I use 20W 50 motor oil and third quart of Lucus stabilizer.

[@D3Sshooter]

works good

[@billywhizz98]

Great video Steve and thanks for telling us about the difference in the oils viscosity that I wasn’t aware of

[@D3Sshooter]

My pleasure

[@ipanemabeach2266]

Hi Steve, what about the overdrive on my GT? Would the GL4 gear oil be appropriate? Thanks!

[@D3Sshooter]

I would say so, however if you drive a standard MGB, just use engine oil 20w50.. that is what they were build for..

[@ipanemabeach2266]

Thanks for a speedy reply! Just a stage 2 head, tubular exhaust manifold, K and Ns etc. I use Miller’s 20:50 mineral. All the best!

[@dopefish93]

I have the 70-71 4 speed overdrive gearbox that has the painfull gearbox fillpoint. Its behind the center console in the floor...

[@brianmac8260]

Same Slave as Rover P6, could you show how to bleed properly and the push-rod settings? Cheers Steve.

[@asciimation]

It's easy to get caught out on the viscosity numbers difference between engine and gear oils if you don't know about that. I use Penrite vintage and classic oils in my cars. It's easy to find in NZ as it's Australian.

[@D3Sshooter]

TXS

[@michaelmenard8913]

Redline MT90 here in USA !! Warm up the diff oil in hot water? Want to see how your rear sway bar is connected/mtd.

[@D3Sshooter]

Just room temperature, 25 C That rear sway bar is connected in a special

[@W0uter1992]

Normally the 4 synchro gearboxes have steel synchro's and wont be affected by the sulfur in the oil. Nevertheless I would not risk it as the shifter forks are brass. If you have an overdrive gearbox the best oil would be a non-detergent oil as the detergents can affect the operation of the overdrive. SAE 30 non-detergent oil works best for an overdrive gearbox (as recommended in the workshop manual). I enjoyed all the MGB video's, great job!

[@D3Sshooter]

Indeed Sulfer and phosphor additives will affect all yellow metals, thus also brass

[@marchutchings8834]

19mm spanner on an MGB? Do you have another gearbox installed? Ie 5 speed Japanese. Great video, never heard of engine oil in gearbox before. Your videos are informative. Kind regards

[@D3Sshooter]

Yes and yes

[@janbrouwer3842]

Nice intro Steve!

[@D3Sshooter]

Thanks!

[@randomguyjustpassingby]

When I was studying in an automobile transport university, I was told that yeah, definitely, sulfuric and phosphorous additives in GL-5 react with non-ferrous metals in the gearbox, so GL-4 is a better option. However, for the rear axle and the hypoid inside, which always works in a kind of friction and slipping manner (due to the design), those additives are must-have. They help oil withstand extreme contact pressure and enhance wear-resistance. And obviously, we don't have brass/bronze synchros in a rear axle. To be more accurate, these additives are not only must-have, they are mandatory for somewhat normal final drive lifespan. So GL-4 in the hypoid rear axle is clearly a "no" (for me, at least) (P.S.: for FWD cars with the cylindrical gear final drive and differential in the same housing with the gearbox, GL-4 is a recommended choice, since the final drive isn't hypoid)

[@MikeAarset]

This just blows my mind. I have always been told to use 30W or 20/50W engine oil in my bugeye transmission. But thanks to your video I did my own research and of course you knew exactly what you were talking about. Not that I was questioning you :) . Thanks again to all the great vids. I might try Red Line MT-90 75W-90 GL-4 in my transmission. Need to replace the rear seal first though.

[@fireblade9005]

Thanks Steve ..Great video ..jus a question if I was to turn the prop how much end 'play' should the diff have (ive got the banjo type on my 1966 MGB)

[@stephenfrench4417]

very informative i do just wonder why the manufacturers did not make removable plates in floor plans with the filler ports at the top of the diff or gear box

[@D3Sshooter]

Its a common issue with so many cars, where designers forget about maintainability access

[@geoffreymills9932]

I'm really wondering what happened to old rusty, were there any more videos on the finishing

[@D3Sshooter]

Geoffrey, its still here and will be back .... just a bit to cold to work on bare metal for the moment

[@jakleo337]

Two thumbs down on the snarky intro graphics. (I'll hit the like button anyway)

[@michaelmenard8913]

I concur ! Goofy intro

[@m.b.smoshitoa8325]

Brother just leave the channel if you feel so. We learn and we learned a lot from Steve. Don't annoy us please. We are concerned about the content not graphics. MBS Moshitoa south Africa

[@drewpierce2273]

Good practical advice, Steve.

[@D3Sshooter]

Glad you think so!

[@sonyhk3824]

Nice job 👍 Steve. Cheers

[@D3Sshooter]

Thanks 👍

[@54mgtf22]

Love your work 👍

[@D3Sshooter]

Thank you! Cheers!

[@livetillyoudielovelife2299]

Always take the filler plug off first

[@michaelb7071]

You can fill via the drain hole also, so no worries.