Gear box oil

[C Kyte]

Hi I see someone mentioned using Redline MT 90 oil in all syncro box. Who makes this oil, I have my engine out and gear box stripped and all parts are in excellent condition. Good. Interested in oil.

Chris

[angelw]

Hello Chris,
You will get it from Super Cheap Auto, or Autobarn. You can have a one U.S. Gallon (3.785 litres) container of it delivered to your door for AUD105.00 via eBay.

Regards,

Bill

[C Kyte]

Thanks for that Bill, do you use it.

Chris

[angelw]

Chris Wrote:

do you use it.

Hello Chris,
I provide a Gearbox Repair/Rebuild service as part of my E Type Restoration business and use Redline MT 90 in all gearboxes I rebuild. Following are a couple of pictures of a completed S3 Gearbox nearing being ready ship.





Regards,

Bill

[PeterCrespin]

I never ship with the stick attached. Have seen two top covers snapped off by rough handling. Agree on Redline and also found Castrol synthetic gave a noticeably smooth change.

[angelw]

Peter Wrote:

I never ship with the stick attached. Have seen two top covers snapped off by rough handling.

Hello Peter,
The pictures were taken for the benefit of the client, so he could see his finished Gearbox. The Gear Stick is removed when finally packed.

[malcolm]

I've been told to use engine oil (20/50) in the gearboxx - any merit in that?

[abowie]

I've been told to use engine oil (20/50) in the gearboxx - any merit in that?

Who told you this? What evidence did they offer to support this?

[malcolm]

They didn't offer any Andrew. Just said "I always use...20/50"
As you will know, I'm not good at this sort of thing - is it duff info?

[mgcjag]

Malcolm....engine oil in engine.....gearbox oil in gearbox

[malcolm]

On that point, does redline MT90 mix with other oils? I don't mean engine oil ( ) but other gearbox oils?
Not sure what's in there at the moment so if I top up with MT90 I might be mixing

[rswaffie]

Hi Malcolm
I would not personally mix the oils. Drain as much out as you can and fill with fresh. Otherwise, particularly if you have engine oil in there, there would be no benefit from using the MTL.

[abowie]

They didn't offer any Andrew. Just said "I always use...20/50"
As you will know, I'm not good at this sort of thing - is it duff info?

My apologies for sounding terse. The great thing about this forum is that at the end of the day we're all amateurs.

My MGA box used engine oil, as recommended by the manufacturer. E Type boxes, AFAIK, don't.

Jaguar recommended a variety of 90 weight gear oils. My personal experience with Redline MT 90 has been positive, and many others have found the same. That's the oil I as a rank amateur would recommend.

Regards,

[angelw]

Malcolm Wrote:

I've been told to use engine oil (20/50) in the gearboxx - any merit in that?

Hello Malcolm,
Not really. The slipperiness and load bearing characteristics of the oil is rather important with a synchromesh Gearbox; far more so than its viscosity. Use oil with too high an Extreme Pressure additive and the Baulk rings will not grip so well. EP additive is used to prevent adhesive wear and protect the components when the lubricating oil viscosity can no longer provide the necessary film thickness between surfaces that are highly loaded and is generally heat activated. Although many engine oils have EP additives, they are seldom of the correct type and level for Gearbox applications.

Regards,

Bill

[Tom W]

The 3.8 workshop manual recommends some engine oils for the Moss box. The all synchro box uses gearbox oil.

[malcolm]

Thanks all for the replies. MT90 it is!

[lopena]

Malcolm:

As detailed in other threads on this Forum, just be advised that Redline MT90 will likely increase the size and number of leaks from your gearbox (due to its thinner viscosity). I’m perfectly willing to put up with a few little puddles of gearbox oil on my garage floor in exchange for much smoother shifting with my Moss gearbox.


Alan
N.J.

[Mark Gordon]

No leaks with MT90 after 11 years in my all synchro box.

[johnetype]

I've put MT90 in two gearboxes, one Jaguar, one Austin both on old oil seals and both have leaked profusely with MT90 when they didn't before.

Changing back to EP90 has only marginally improved the leaking which makes me ponder if it's not just the viscosity but an additive that doesn't agree with old seals.

Obviously I need to fit new seals, it's just not an easy job.

My Jaguar box poor second gear synchro was worse on MT90. Again, no reason to expect miracles and there weren't any.

[ralphr1780]

Malcolm:

As detailed in other threads on this Forum, just be advised that Redline MT90 will likely increase the size and number of leaks from your gearbox (due to its thinner viscosity). I’m perfectly willing to put up with a few little puddles of gearbox oil on my garage floor in exchange for much smoother shifting with my Moss gearbox.


Alan
N.J.

Alan, for Moss box the recommended grade is MTL.
MT90 is recommended for the later synchro boxes.