• The Roadster Factory Recovery Fund - Friends, as you may have heard, The Roadster Factory, a respected British Car Parts business in PA, suffered a total loss in a fire on Christmas Day. Read about it, discuss or ask questions >> HERE. The Triumph Register of America is sponsoring a fund raiser to help TRF get back on their feet. If you can help, vist >> their GoFundMe page.
  • Hey there Guest!
    If you enjoy BCF and find our forum a useful resource, if you appreciate not having ads pop up all over the place and you want to ensure we can stay online - Please consider supporting with an "optional" low-cost annual subscription.
    **Upgrade Now**
    (PS: Subscribers don't see this UGLY banner)
Tips
Tips

Transmission with Overdrive - Which Oil to Use

gonzo

Jedi Warrior
Country flag
Offline
Apologies for raising an old subject, but i need clarification on forum search findings:

For those running Original OD Transmissions, which oil do you choose to use? I use Castrol GTX 20W 50, same as for engine, but ready to make a change to RedLine MT 90 based on forum discussions / stories. MT 90 and Castrol GTX on shelf ready for action. Any suggestions would be appreciated. GONZO
 

Healey Nut

Luke Skywalker
Country flag
Offline
If 20/50 was good enough when they built it , its good enough now . Why change
 

TimK

Jedi Knight
Silver
Country flag
Offline
30 wt. non detergent
 
OP
G

gonzo

Jedi Warrior
Country flag
Offline
Thanks. My old standby, Castrol GTX 20/50, will go in the trans like before. Last time I used 30W non detergent was in my '65 Corvair Corsa air cooled boxer engine, so I understand the rationale here. Gonzo
 

Keoke

Great Pumpkin
Country flag
Offline
Same as engine 60 W Valvoline VR1
 

British_Recovery

Jedi Warrior
Bronze
Country flag
Offline
Some thinking behind the choices - 30 non-detergent vs 20/50 GTX - has to do with the metal used in the synchros.
Yellow metals - bronze, brass - use the non-detergent 30 wt. (earlier cars - side shift and some center shift).
Steel - 20/50 engine oil. (Later center shift).
 
Last edited:

vette

Darth Vader
Country flag
Offline
I was pretty sure that the Healey manual calls for 30w motor oil. Non-detergent would also be the smarter choice. I would concede that some modern oils such as Red Line as advertised might provide smoother shifting especially in colder weather but I agree with Healey Nut if what ever was spec'd when the car was built and of coarse if there have been no perceptible incidences of failure then the original stuff is what I use. My car usually doesn't get fired up when ambient temp is below 50*F.
I also have OD. :smile:
 

RAC68

Darth Vader
Offline
This is a discussion that seems to come up quite frequently with quite a variation in oil use type. Although, as British_Recovery has indicated, metal types used in the transmission should be considered when selecting lubrication oil for the trans/OD, I would also extend that NON-Detergent oils were recommended by Healey to allow metal debris to fall out of oil suspension and collect in the pan. Detergent oils were designed to keep debris in suspension and eliminated through the use of a filter as in the engine. Since there is no filter in our trans/OD, keeping debris in oil suspension can only present an extended risk.

As for oil choices, I use Redline MTL synthetic which is more of a gear type oil with similar viscosity to a 30W engine oil. Although synthetic oils have a greater probability for finding a path to leak out, I have found little fluid loss over the years and have enjoyed smooth reliable shifting and OD responsiveness. Although others may prefer using engine oil or even Automatic Transmission Fluid. As I see it, the construction of the Healey transmission/OD is the stimulant for their non-detergent recommendation and although others may used the same OD and recommend different lubricants, it also conforms to the requirements of their transmission as well as OD.

My thoughts,
Ray(64BJ8P1)
 
Country flag
Offline
I switched to Redline MT 90 over 10 years ago. I love it. It is true that it leaks out no mater what you do. It can be had on line or Ebay for a more reasonable price. Check Summit Racing too. Use a drip pan if you don't already. The stuff is SLICK! I get about a 3-4 inch drip in about a months time. (The mystery is why the dip stick never shows any loss).
 

roscoe

Jedi Knight
Silver
Country flag
Offline
No mystery. A teaspoon of oil will keep your spot on the floor fresh and shiny for months. If only oil evaporated like alcohol. Fires would be more likley but we wouldn't have those gol darn spots....
 

pan

Jedi Warrior
Country flag
Offline
I use Penrite Gearbox Oil 40 which I believe is an Australian product. As Ray says, I think it best to avoid multigrade detergent oils. I went for the slightly heavier weight because of the warm Queensland climate, where I live.
 

twas_brillig

Jedi Knight
Country flag
Offline
Redline recommends MT-90 GL4 (according to my notes - I've standardized on Redline for all the 'vintage' transmissions and differentials we own). They recommend it for Spridget 4 speeds, AH 3000 o/d transmissions, as well as the replacement Datsun and Toyota 5 speeds. Doug
 

Editor_Reid

Moderator
Staff member
Platinum
Country flag
Offline
(The mystery is why the dip stick never shows any loss).

I have long wondered the same thing. I have three drip pans under my BN2, end to end. I get puddles of at least three different fluids there (the car apparently leaks fluids that I don't even add!), and the quantity would suggest that I need to add this and that, here and there, more often than not. However, year after year, no loss shows on the dip sticks.

How they do it, I'll never understand.
 

RAC68

Darth Vader
Offline
I noted that some use Red Line MTL, as I do, and some use MT90. I looked into the differences and found that the MTL and MT-90 are both GL-4 gear oil and differ in viscosity with MTL providing 70w at low temperatures and close to 85w at high (SAE 5w30/10w30 engine oil) while MT90 performs through a 75w - 90w range and meant for warmer climates. Since I do drive my Healey until the snow and ice show up, I use it through a more diverse temperature range then most and find the lower viscosity of the MTL will maintain the smooth operation of the Trans/OD on cold days as it does during the hot NJ Summers.


Happy St. Patrick's Day,
Ray(64BJ8P1)
 
OP
G

gonzo

Jedi Warrior
Country flag
Offline
Forgotten that OD equipped transmissions has TWO drain plugs, or perhaps I had never noticed! So this time the entire trans and OD were properly drained by pulling both plugs. Followed by fresh oil (Castrol GTX 20W 50). Shifts nicely- Red Line MT 90 next fluid change.

On a related subject, using 1st gear on take off now and holding each gear a lot longer with the 3.5:1 rear end installed. Holding 4th gear doing 60 / 65 MPH @ 3000 RPM. A few more runs with the GPS are needed to determine how far off the speedometer is, but at the moment it's looking like 5 to 7 MPH under. I'm liking this new ratio and a fresh rebuilt diff. GONZO
 

vette

Darth Vader
Country flag
Offline
Hi Gonzo, when you say "holding 4th gear doing 60/65 MPH @ 3000 rpms" do you mean straight 4th or 4th with overdrive.
Thanks.
 
OP
G

gonzo

Jedi Warrior
Country flag
Offline
Hi Gonzo, when you say "holding 4th gear doing 60/65 MPH @ 3000 rpms" do you mean straight 4th or 4th with overdrive.
Thanks.

That's straight 4th gear without engaged OD. The 3.5:1 rear ratio allows to hold 3 and 4 gear longer on the same stretch of roadway which used to demand 4 gear OD. :eagerness:
 

glemon

Yoda
Country flag
Offline
I have used 20w-50,10w40, GL4 gear oil, and probably a few other things in my old 100 and other old British car with overdrive gearboxes. I have never noticed much difference, except some of the thicker stuff felt thicker when I used to drive year round in extreme temps.

What I have read has convinced me that a straight weight non detergent is a better choice in a gearbox than multi-viscosity detergent oil. I have been using that more as GL4 has become harder to find.

I like what I read about the Redline products, but most everybody says they have a propensity to leak. My gearboxes all seem to have a similar ropensity. Putting the two together has not seemed like a good idea.
 
Similar threads
Thread starter Title Forum Replies Date
AUSMHLY Flushing the Transmission/Overdrive Austin Healey 7
T Weight of BJ7 Transmission/Overdrive Austin Healey 10
J Transmission and Overdrive Rebuild Austin Healey 6
G Wanted TR3 Overdrive Transmission Triumph Classifieds 2
KVH TR4/4A Transmission and Overdrive Capacity Triumph 6
Moosca TR2/3/3A TR3 Overdrive Transmission Verification Triumph 5
Marvin Gruber General TR Overdrive transmission serial number Triumph 1
P 100M overdrive disengages on hot engine/transmission Austin Healey 9
L Transmission BN2 with 28/1292 overdrive Austin Healey 3
Got_All_4 TR2/3/3A Fitting the original tr3 transmission cover over a tr6 overdrive Triumph 9
D TR2/3/3A TR3 Overdrive to transmission mating problem Triumph 8
W TR2/3/3A Looking Into Overdrive Transmission Triumph 16
T TR2/3/3A Will Spitfire D-type overdrive work in TR3 with TR4 transmission? Triumph 3
S TR2/3/3A overdrive transmission, cosmetically clean Triumph 12
P Mysteries under the BJ8 transmission tunnel, speedometer cable, overdrive and gerabox Austin Healey 1
AUSMHLY Flushing the transmission and overdrive Austin Healey 6
drooartz Servicing transmission and overdrive MG 9
J Overdrive transmission question Triumph 4
KVH TR4/4A TR4A Transmission Overdrive Plug Leak Triumph 13
TR3TR6 TR4/4A TR4 Transmission Question [non overdrive] Triumph 11
John_Mc MG overdrive transmission on CL MG 2
N Seating The Ball On An Overdrive Transmission MG 10
5 Water in overdrive and transmission Austin Healey 4
Johnny Removing Overdrive from transmission. Austin Healey 1
V a type overdrive transmission Triumph 8
C Transmission conversion for overdrive what to do? Austin Healey 15
Mickey Richaud Transmission/Overdrive Wiring MG 3
6 Overdrive Transmission MG 16
7 Overdrive Transmission MG 1
Jim_Gruber Correct Transmission Oil for Datsun 210 5-speed Spridgets 1
Got_All_4 General Tech TR6 Transmission Troubles Pops Out of 3rd gear Triumph 2
mctriumph SOLD!! Tr7/ Tr8 transmission Triumph Classifieds 0
C TR6 Transmission Number Meaning Triumph 5
R 100-4 Transmission Austin Healey 1
S TR2/3/3A Rebuilding a tr3 transmission and second gear, Triumph 57
S TR2/3/3A turn a tr3 non-full syncro transmission into a full syncro Triumph 3
J TR4/4A TR4A automatic transmission conversion Triumph 6
Popeye TR4/4A Transmission noise - intermittent Triumph 22
D XK150 Transmission Input Shaft Jaguar 1
A TR2 Transmission overhaul Restoration & Tools 0
E General MG Transmission Fluid Level MG 2
B Transmission Gear Lockouts Austin Healey 8
K Putting a Getrag 5 speed OD transmission in a Jaguar Mkll ? Jaguar 4
AUSMHLY Transmission Noise Austin Healey 11
KVH General TR Transmission Problem Triumph 3
T Looking for "BillMs rear transmission mount" Spridgets 2
T For Sale Excellent Original 1968 TR250 Frame with Engine & Transmission Triumph Classifieds 6
D TR2/3/3A Torque for bolts back of transmission ? Pl Triumph 0
bighealeysource Side-Shift Transmission Austin Healey 13
D transmission conversion Other British Cars 1

Similar threads

Top