Transmission / Overdrive: Oil for a T-86 with over drive

[Drifter22]

Dose anyone know what oil you should put in a B-W T-86 w/od. A guy told me last night it should be 90wt gear oil, but I have it copied from an article that it should be 30wt non-detergent motor oil. The article said there should be no additives as they will cause problems with the over drive one way clutch.

Thanks, Gene

[gordr]

90W GL-1 gear oil is fine. Avoid anything labeled as "hypoid oil" or with an EP rating. I have had good luck with using a good quality 15W-40 or straight 40W motor oil, too. I find the syncros work better with a lighter oil.

[Flashback]

This is the closest thing to what's described in the owners manual, I can find. This is what I use.

[StudeRich]

I might add that Farm Supply Stores in Rural areas carry "Traveler" Brand.
But NAPA GL-1 Gear Oil is "NAPA" Brand.

[silverhawk]

When I was still running a T86/overdrive in my Lark; I used to cheat and run the GL4/GL5 from CarQuest. Reasons being, we got a sweet deal through the business account due to how much we purchase. Next, after a rebuild, I did run the correct gear oil for a while; and there wasn't any difference in shifting or potential gear whine until I blew it apart. (Long story on the whine) Running the same stuff on my new T85C/overdrive as well.

Just my opinion; but learned from experimenting on what worked for me.

[62champ]

I use a full synthetic in my OD transmissions - perfectly good with white metals and really noticeable on those cool mornings (maybe twice a year in FL?).

[Drifter22]

Thanks for all the good information. I have been running Tractor Supply HD 30wt for about 3000 miles and it seem to run very well. I just found a top load shifter and got installed today. That was a real job making the little arm off the rear shifter fork to lock out the over drive for reverse gear.

[jackb]

....I used to find motorcycle 50wt for an old OD tranny.......worked ok except when cold....let it idle some and stay 1st gear/reverse a bit longer

[Drifter22]

I got my transmission back together, found the 90wt,G-L1 oil at Tractor Supply and was going to take it for a drive and it wouldn't move! I shifted it into 1st, 2nd & 3rd and nothing, you could hear the gears running. I put in reverse and it backed up. So I pulled the over drive control out and it would drive like it should. Has anyone ever had this happen? Any ideas guys? I had this 3 speed rebuilt by a transmission company a year ago and installed all new wiring, switches and relays and it has been working good. It had 3 on the tree, I always wanted a floor shift and I found a top loaded. So I pulled the tranny, had Astro take the the internal shifting forks out of it and after big ordeal I got a little arm welded on the reverse shifting fork to lock out the over drive so I could back up. I appears that is working right. Have you ever heard of this? Any help would be appreciated.

Thanks

[Drifter22]

I got my transmission back together, found the 90wt,G-L1 oil at Tractor Supply and was going to take it for a drive and it wouldn't move! I shifted it into 1st, 2nd & 3rd and nothing, you could hear the gears running. I put in reverse and it backed up. So I pulled the over drive control out and it would drive like it should. Has anyone ever had this happen? Any ideas guys? I had this 3 speed rebuilt by a transmission company a year ago and installed all new wiring, switches and relays and it has been working good. It had 3 on the tree, I always wanted a floor shift and I found a top loaded. So I pulled the tranny, had Astro take the the internal shifting forks out of it and after big ordeal I got a little arm welded on the reverse shifting fork to lock out the over drive so I could back up. I appears that is working right. Have you ever heard of this? Any help would be appreciated.

Thanks

[Dwain G.]

Who is Astro, a transmission shop? They must disassembled the trans to do the shift levers. Ask them what they used to hold the one-way clutch rollers in place.

[Drifter22]

Yes, there a transmission parts and rebuild company here in Florida. Yes they took it apart and removed the shift levers on the side of the transmission. I modified the low/reverse fork on the top loader to lock out the over drive in reverse. I took pictures and made a little drawing of it. If interested I could email to you. It's not a great weld job, but it will hold and the drawing was not done by an engineering company, but you can make it OK. I wonder why my last post, posted twice?

[Dwain G.]

Gene, not sure you understood what I was asking. I'm saying you should call the trans. shop and ask what they used to hold the rollers of the overdrive one-way clutch in place during reassembly. Some people use heavy grease, some use a rubber band. Either one should melt away pretty quickly and allow the rollers to grab the clutch drum.

[Drifter22]

Yes I did call them today and they said they used a different grease then they have been using, but he thought in would flush out if I drove it for a few miles. Well I took it for a drive with the O.D handle pulled out and I went about 4 miles and it just acted like I took it out of gear. I put it in 2nd and nothing. I pulled off the road and went thru all of the gears and it would not move, with O.D. in or out. So I call a friend that has a garage and he sent his roll back out and took me home. Will waiting I called Astro and he was stumped, but said bring it up and he'll fix it for me. Of coarse that's easier said then done.