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Another transmission oil question

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AUSMHLY

AUSMHLY

Yoda
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Hi guys,

Currently I have Redline MT90 in the transmission and on the floor. Not happy about how much it leaks, but I am happy with the shifting and overdrive smoothness.

Here's today's question.
I used to use GTX 20/50.
Anyone using GTX 20/50 synthetic in the transmission?

Maybe GTX 20/50 synthetic would be compromise between regular GTX 20/50 and Redline MT90? Maybe not leak as much as MT90?

Drive it like you stole it.
Roger
 
Nice article here, scroll down:

https://www.quantumechanics.com/categories.php?op=newindex&catid=11

I have run straight weight non detergent and multi weight conventional (20w-50) in O/Ds with no ill effects. The above article indicated pressure drops with a multi weight oil due to oil frothing, but he tests with a 10W-30 vs. a stright 30 weight, then they test a hypoid 90w gear oil (generates too much pressure) and a synthetic (no news to you, leaks).

Anyway interesting reading.
 
Interesting article.

Now I have two questions.

1. Anyone using GTX 20/50 synthetic?
2. Any recommendations on what 30 non detergent to use?

Roger
 
AUSMHLY said:
Interesting article.

Now I have two questions.

1. Anyone using GTX 20/50 synthetic?----Not Me
2. Any recommendations on what 30 non detergent to use? Valvoline VR1
---------------------------------------------Keoke
Roger
Click to expand...
 
30 non-detergent is becoming harder and harder to find. I buy it from NAPA by the case (It's the engine oil in my Studebaker). I just checked and it's the "Premium Performance" store brand. I'v nver hard the old girl (aka car) ever grumble about it.

Jody
 
Roger, I believe the 30 wt non-detergent is used to keep the particles in the gear box from being in suspension. Metal particles drop to the bottom and stay there. (picked up by the magenets, if lucky). Detergent oils are made to suspend the junk when used in the engine so they get trapped in the oil filter to be tossed out when the oil is changed. British cars have historicly used 30 wt non-detergent. Personally, I use MT90 and love it.
 
tahoe healey said:
Roger, I believe the 30 wt non-detergent is used to keep the particles in the gear box from being in suspension. Metal particles drop to the bottom and stay there. (picked up by the magenets, if lucky). Detergent oils are made to suspend the junk when used in the engine so they get trapped in the oil filter to be tossed out when the oil is changed.
Click to expand...

I'm not following you TH.

Lesser of two evils? Particles drop to a magnet with non-detergent, or they are suspended in detergent oil?

Sounds like your saying detergent oils are meant for engines and not trannys? That the tranny magnet will not pick up junk from detergent oil being in suspension?
 
Hi Roger,
I can't remember if it was Dave or Keoke that said to stay away from multi viscosity motor oils in the transmission / overdrive ?
Ed
 
Guys, I'm just not happy with the amount of Redline MT90 on my garage floor.
What can I try that will not leave these big puddles?

My three Healey mechanics say use GTX 20/50.
Keoke, you use Valvoline VR1 30 non-detergent. Is it synthetic? I would assume your car leaves a bit of a drip mark. Any idea of the size it leaves compared to Redline, or GTX 20/50?
 
AUSMHLY said:
Guys, I'm just not happy with the amount of Redline MT90 on my garage floor.
What can I try that will not leave these big puddles?

If you have big puddles of oil on the floor you may need a omp;ete new set of joints with sealer installed.

My three Healey mechanics say use GTX 20/50.---????

Keoke, you use Valvoline VR1 4o or 60 non-detergent. Is it synthetic? :nonod:

I would assume your car leaves a bit of a drip mark. :nonod:

Any idea of the size it leaves compared to Redline, or GTX 20/50?--------------0" Sq,

Note: I saw no point in carrying two types of oil when I travel oil seight is seasomal and Non Detergent.---Keoke--- :cowboy:
Click to expand...
 
Roger, you are correct as you quoted me. Detergent oil keeps the metal particles floating where they can get stuck in places you don't want. That is the design. Thats why British car manuels specify 30 wt NON-detergent. There is a magnet in the system behind the large brass plate at the bottom of the gear box. You may wish to tighten it with the proper wrench. (I just bought one from Nock for about 50 bucks along with a new gasket in an attempt to keep the oil on the proper side). Multi-wt has always been questionalbe in the gear box in the 40 years I've had British cars. And the temperature change is not as extreem as in the engine and that is what multi grade is for, temperature extreems. But thats why they make different flavor ice cream. We don't all like vanilla. Others will disagree with me. I would rather add MT-90 and clean up the drops on the floor than do gear box work.
 
I don't disagree with you Rich. I like vanilla ice cream (vanilla bean). It's really good with Godiva liqueur.
 
AUSMHLY said:
Th, you and I are both using MT90, which is a multi-weight. Isn't Redline a detergent?

:savewave::yesnod: MT90 has an equivalent motor oil viscodity of SAE 10W/20/40 or Gear Oil 75W 90 GL4 rating, However, the additives used in Red Line are not corrosive like dino oil additives. Dino oil additives can attack certain metals used in transmissions. So the Brits and Keoke not knowing what tranny you might have or its metallurgical content specify Non Detergent dino oils. OTOH, Red Line excels in the production of synthetic lubricants which include MT90.
Click to expand...
 
And if you are using gear lube remember it has the added feature of being formulated for shear wear protection. Not really needed in trans gears, but never hurts. Some GL-5's will attack brass. Most synthetics do not.

Like Keoke said the comparable viscosity in gear lube is the same as most engine oils. Engine multiviscosity oils are not recommended(though a lot of people do use them) in most lbc manual transmissions....
 
Roger, I was not aware of the multi grade of Redline. I started using it after Dave Russell recommended it when I had shift problems. I never questioned it. But I like it. I can live with the drips. I bought a case of 12 at $8.50 each. Should take years to drip it all out. And I use an oil pan.
 
For those who use Redline, has anyone tried a gasket sealer on the fiber washers instead of dry? If so what have you used and how effective is it?
 
I use Permatex Aviation Form-A-Gasket. Don't know well it's working, haven't parked it on any "virgin" pavement :wink: I've previously used thread sealant, which seemed to work well.

The problem with fiber washers--like the ones in the fuel system and O/D--is that they compress over time and the bolts/caps need to be re-torqued. Hylomar should work good as it doesn't harden.
 
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