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Tranny oil-did I screw up?

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TRclassic3

TRclassic3

Jedi Trainee
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After having the tranny out over the winter I went hunting for GL-4 oil and the only thing I could find(at least easily) was a gl-4/gl-5 syntheic by Royal Purple. At the time I was led to believe that the biggest concern was GL 5 being potentially corrosive to the brass gears. Royal Purple specifically stated that it was non corrosive, so I went ahead with it. Now i'm reading that synthetic shouldn't be used because it is too slippery and the synchros won't work right. Should I change it out to dino based?
 
TRF sells Castrol GL4 for the TR gearbox. I've never seen it in a store but CarQuest said they could order it for me.
 
Napa can order it for you.
 
There are some good threads on this subject in this forum. Mostly the titles involve Differential Oil or Gear Box Oil, but if you do some searches you will find some good info about the subject.

My take-away for all this discussion is that, for peace of mind, if its not much effort to change I would drain the gearbox and go back to GL4. It would seem that corrosion takes a long time to have an effect, and maybe you would have changed out the gearbox fluid before that happens anyway, but it just seems prudent to change it.

There are a number of GL-4 gear oils available, although you will may have to go to a specialty place to find it on the shelf.

Napa Online lists SL24229 (Sta-Lube 85-90 wt GL-4), or SL24239 (1 gal size). They should have it in stock or can order it for you.

Pennzoil #56076 is a synthetic GL-4. Good for diffs, but maybe too slippery for the gearbox. Redline offers GL-4 also.

TRF sells GL-4 (non-synthetic I believe) online also.
 
Ed - I just saw GL-4 at Sears Hardware.

Off the topic: you mentioned "dino based"

Where'd you hear that expression? When I was a kid my dad worked for Sinclair. Their two gasolines were Dino and Dino Supreme. And since the mid 1930s Sinclair had promoted miniature dinosaurs in its PR.

That was a *long* time ago for me.

Tom
 
Try a local speed shop or engine shop. They may have REDLINE.
I can attest to the "too slippery" comments. I changed the gearbox oil in the wife's Miata to Mobil 1 gear oil. She complained that it was hard to shift into 2nd. I test drove it and found that indeed it was hard to go into second without either a little crunch or double clutching. I drained the oil and refilled with a mixture of REDLINE a coctail of MT90, 75W90 and few ounces of their Shock Proof gear oil. The recipe came from a Miata racer/ engine builder. It solved the hard shifting problem.
 
Crypty is running just fine and dandy on
Super Tech gear lubricant SAE 80W-90 GL-5.

DPO Pedro was running with sawdust and corn
oil in the tranny.

d
 
Thanks to all for the advice and information. I will take it to heart.

Tom,
I do recall the Sinclair Dino, but I'm not sure where I heard it, other than just general dicussion and refering to petroleum based fluids.
 
Not British (by a long shot) but my Nissan truck specified GL4 for the tranny. I looked long and hard, and couldn't find any. I eventually used Royal Purple as well, and 2 years later, all is well.
 
Get some GM Syncromesh fluid. It's available at GM dealers (duh!) plus is also available from Pennzoil, Valvoline, etc. It seems to be a great choice for all brands of OD and non-OD transmissions. It's the recommended fluid for Laycock de Normanville "Gearvendors" overdrives...the 'Tuner' guys use it in their Riceburners...hot rod guys have discovered it works great in everything except the early Ford (pre-48) manuals...it's about a 50W and is what GM has been using in all of their manual transmissions for several years now.
 
At a gearbox tech session for Mason-Dixon TRA, Jack Merriman said to always use SAE 30 motor oil in my gearbox. Yes, that MOTOR oil. So that's what I have always used.

The SAE uses different ways to grade gear oil and motor oil viscosity, so SAE 30 motor oil and SAE 90 gear oil are close to the same viscosity.
 
So John, if that's the case why not just use the SAE 30 in the steering box as well?
 
Dunno, Ed. Point taken.

I've told you more than I know about this already!
 
I would think that SAE 30 wouldn't be right in a steering box for two reasons...It will probably leak a little more than normal if the seals aren't up to snuff and SAE 30 isn't designed to absorb 'shock loads' like you get in a R&P. A transmission with bevel-cut gears is a lot easier on the lube than a diff.

One think that DOES decrease steering friction is a synthetic 80W-90 lube...especially in cold weather. I used this in TS74011L as I usually drove the car until the first snow and routinely had it out on mild winter days. I also used this in class 8 trucks in the days before we had power steering...huge difference at -10 F.
 
1. Have used Redline synthetic in TR gearboxes (non-OD) for 10 or 12 years w/o a problem. Perhaps it aggravates worn synchros though.

2. I think gear oil has additives that are specifically for the high pressure contact between the gears of a diff or steering box... motor oil in those applications may be less than ideal.

3. For 20 years or so a little green Dinosaur has ridden on the dash of our VW bus since we got him at a promotion at the Sinclair station in Hanksville, UT. I still always gas up there when passing thru the Canyonlands area so I guess their promotion worked.
 
A footnote to this discussion. Took the car out Sunday and put 70 miles on it. The tranny was not as smooth as it was before. It was OK, but I could feel the difference, particularly downshifting or going to reverse. I've order Sta-Lube GL-4 on line and will change out the Royal Purple.

Guess the proof is in the drive.
Thanks again to all who offered advice.
Ed
 
I've run Redline MTL in mine from when it was rebuilt 4 years ago. Works fine.
 
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