Just finished a power train rebuild for the 66 Toronado and even the trans shop is lost for corret lube in the diff. The shop man and owners manuals have very stern warning to use ONLY the correct GM part lube, NOT conventional (I assume and 80/90 gear lube). But the Buick and former Olds dealers in town say that number in the manuals is a "touch-up paint". (Is this one of the reasons Olds div. got axed????) I'm trying to get this old guy on the road. Any references back to this early FWD Olds?
Diff lube for 66 Olds Toronado
- Thread starter WaterfordBob
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Does the diff share fluid with the tranmission in these early big FWD's?
The diff cavity on the Toro is separate from the trans. The only access is a single plug for fill and level check. Otherwise you have to remove the diff housing (cast iron and includes the gearset) from the aluminum trans case.
THe fluid that came out was rather 'thick' amber/brown oil.
If you look at a service manual diagram don't be misled because the trans fill/stick tube passes through a boss in the CI diff case but is gasket sealed away from the diff cavity and passes on into the trans sump. Kinda unique.
THe fluid that came out was rather 'thick' amber/brown oil.
If you look at a service manual diagram don't be misled because the trans fill/stick tube passes through a boss in the CI diff case but is gasket sealed away from the diff cavity and passes on into the trans sump. Kinda unique.
My 1978 application guide shows 80W-90 gear lube.
Naturally, AMSOIL recommended synthetic.
Naturally, AMSOIL recommended synthetic.
Modern Syn 75W-90 should work fine.
If you want something a bit "thicker" (hate that word, you could try a syn 75W-140.
If you want something a bit "thicker" (hate that word, you could try a syn 75W-140.
It is a separate housing from the transmission (TH400 rotated 180 degrees). The differential is not a standard DANA or GM unit from a 4x4 pickup, but unique Toronado-only. Still, I cannot imagine modern 75W-90 not working in it.
One of those 66 Toronados was "my father's Oldsmobile".
One of those 66 Toronados was "my father's Oldsmobile".
Bob: MYSTIK-JT-7 80w90 gear oil, i have witness this gear oil outpreform every leading synthetic gear oil in the incredibley severe SPICER TEST.
Thanks for the inputs. I'll add that my other investigation (by way of my brother-in-law) who asked an 'old timer' Olds service guy offers that he recalls using 80w-90 with success back in the 60's & 70's.
I'll go with 80w-90. I'll just stew with the mystery that one of the gearheads at Olds got that stipulation in the manuals (and maybe some additional additives in the OEM lube). The Toro diff is fairly unique to GM/US autos in it's planetary setup. But I gotta believe that a gear is pretty much a gear; planet or spider in a similar application.
I'll go with 80w-90. I'll just stew with the mystery that one of the gearheads at Olds got that stipulation in the manuals (and maybe some additional additives in the OEM lube). The Toro diff is fairly unique to GM/US autos in it's planetary setup. But I gotta believe that a gear is pretty much a gear; planet or spider in a similar application.
Here's some additional input I got from a fellow in the Toronado Club. His research showed him that the original lube had some anti-foaming agents in it either because the planetary set was prone to foaming OR it was a 'just in case' addition due to the new design. At any rate, his/their experience shows that the newer (since 1966 lube technology) products are much better and therefore will work okay. I chose some synthetic so I should be super save. Additionally, some time ago, I sent a request to the Oldsmobile Archives; though I havent heard from them yet, I'll add their comments when they arrive.
Is the differential Limited-Slip? If it doesn't have it, it would be a good idea to install it. Good luck!
..I took interest because I enjoyed a 89 Toronado Trofeo (aftermarket Limited-slip installed) and a 92 Trofeo. They were both great cars...maybe even appeared a bit 'ahead of their time' with all the fun gadgetry.
..I took interest because I enjoyed a 89 Toronado Trofeo (aftermarket Limited-slip installed) and a 92 Trofeo. They were both great cars...maybe even appeared a bit 'ahead of their time' with all the fun gadgetry.
A Limited-Slip Differential is a NECESSARY item, especially when in inclement driving conditions. It is embarrassing and makes the vehicle look stupid when an open differential spins only one wheel, which has the least amount of traction. Really, if you are going to all the work of a powertrain overhaul, it would be a VERY good idea to install a limited-slip unit. Good Luck!!
Thanks for the suggestion re limited slip diff. Just to share with you my idea of how this car will now be pampered. NO WAY is it going out in inclement weather after all this work. I have a newer 'technomobile' with fuel injection, AW tires, and modern conveniences for that. BTW here's an old timers story for you.
I remember the time, many years ago, driving this car in a huge, blowing snow storm. Made the trip home okay but the drivway was slighty up hill but the big deal was a drift as high as the hood at the end of the drive. Thanks to a neighbor struggling up the street in his car, I had to stop IN the drift. No problemo, no 'rocking', just ease into the gas and 4800 # of car (60% on the front) and just enough torque and I powered into the drive and garage with no slip no strain. FWD is really a good thing. So are good tires.
For my plans of use, a desire to keep the car orginal to the build specs, and prior experience, I think I'll pass on the 'posi'. Anyway, I haven't researched if there is such a thing for this slightly unique dual plantary diff.
My son put posi into his 96 Gran Prix. Along with a "couple" other mods and he's turning 12.6 sec. ET's. Again, no bad for FWD.
I remember the time, many years ago, driving this car in a huge, blowing snow storm. Made the trip home okay but the drivway was slighty up hill but the big deal was a drift as high as the hood at the end of the drive. Thanks to a neighbor struggling up the street in his car, I had to stop IN the drift. No problemo, no 'rocking', just ease into the gas and 4800 # of car (60% on the front) and just enough torque and I powered into the drive and garage with no slip no strain. FWD is really a good thing. So are good tires.
For my plans of use, a desire to keep the car orginal to the build specs, and prior experience, I think I'll pass on the 'posi'. Anyway, I haven't researched if there is such a thing for this slightly unique dual plantary diff.
My son put posi into his 96 Gran Prix. Along with a "couple" other mods and he's turning 12.6 sec. ET's. Again, no bad for FWD.
Here's the final chapter (for me) of the Toro diff lube research: Just heard from the Oldsmobile Archives about the lube. Their records show the same (obsolete) part number for the lube, no surprise there, and further commented that SAE 90 Multi-purpose gear lubricant is to be used for replenishing the fill. Guess that at least rules out some special formula. I'm sticking with the 74w-90.
Again, thanks for your comments, all of them.
Bob
Again, thanks for your comments, all of them.
Bob
Did you keep those "exciting" drum brakes all around?
The '66 was one great looking car.
I always loved the PR stunt where they hooked up a weight distributing hitch and big travel trailer . . then removed the rear wheels and drove the rig all over the country. A great picture if anyone has it.
The '66 was one great looking car.
I always loved the PR stunt where they hooked up a weight distributing hitch and big travel trailer . . then removed the rear wheels and drove the rig all over the country. A great picture if anyone has it.
Yes, TanSedan, it still has the drum brakes. They look great when painted (atleast close to) factory gray in hi temp paint. My dad (had a '68 Toro) similar experience to the PR you mentioned (whether he was clued by the ad or was just sneaky). He went to pick up a new/used travel trailer. The seller tried to use his RWD, 2WD vehicle and equalizer hitch (yup, it took weight off his drive wheels) to pull it out of a slightly slick, uphill sloping field. Well that didn't work. So dad 'volunteered' to JUST TRY the Toro and with PLENTY of lift on the equalizer - walked away with the trailer as if it was all down hill. Wonder if the seller ever figured out if he was 'had'.
Hey, we oughta share these stories with the Toronado Owners Assoc. or something.
Hey, we oughta share these stories with the Toronado Owners Assoc. or something.
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