Technical saginaw four speed

I just installed my newly rebuilt Saginaw four speed in my deuce roadster. I bought two quarts of Amalie synthetic gear oil for it. I later remember reading something about this synthetic oil causing problems with the brass syncro rings. Is this true? if so what are most guys using today? Thanks Rich

 

Sometimes they won't shift.. If it doesn't feel right try 1/2 AFT and 1/2 90wt gear lube. That what worked for me.

 

Yep

Bones

 

Sta-Lube gl-4, NAPA had it in their warehouse here.

 

Same lube for my Muncie M-20.

https://www.google.com/search?q=mun...j33.14047j0j8&sourceid=chrome-mobile&ie=UTF-8

 

GL-5 has an additive that is not compatible with the non-ferrous material of the earlier transmissions such as bronze bushings and blocker (syncro) rings. From what I have read many newer GL-5 approved lubes have an additive that prevents the newer EP additives from attacking those metals. I suppose that a lube being cross compatible for GL-4 and GL-5 would be acceptable but I'm kind of making an assumption but I would try to research a particular brand to make sure that it will mix with earlier fluids and it is safe for earlier materials.

 

I don't use synthetic anything in my transmission (M20) or rear. For the M20 I went with a mineral-based GL4 that my local speed shop had, may have been a Brad Penn product. Some guys swear by GM Synchromesh fluid that I'd use over a synthetic.

 

Drained the amalie out, siphoned the last out with a piece of 1/4 inch clear hose. All this thru the lower bolt hole, as my trans doesn't have a lower drain plug. I went all over town, could not find any GL4 lube. I read the info on all of the GL5 fluids and they only recommend it for non syncromesh transmissions. These obviously don't have brass syncro rings! I ended up buying Royal purple at $22.00 a quart. It says it is good for all syncromesh transmissions, Hope so! At $22.00 a quart it ought to be good for a lot more that that! Will let you guys know what happens. Thanks Rich

 

If you ever read the description of Royal Purple products it has to be the best invention since sliced bread. The only draw back is the price. They are real proud of their products. I use their products when ever needed.

 

Royal Purple is the good stuff. I've used it in shaft-drive motorcycles for the final drive and it's cut running temps by at least a third. Nope, it's not cheap....

 

I've been using Pennzoil Syncromesh Transmission fluid in transmissions with yellow metal where EP gear lubricants could cause a problem with corrosion.

Bob

 

GL5 and synthetic gear lubes are so slippery that they tend to "over-lubricate" the brass synchro blocker rings. This can cause hard shifting because the lube can't be fully or quickly displaced between the blocker rings and the steel cones on the synchro hubs when the synchronizer attempts to engage. Then to top it off, the additives in some modern lubes will attack brass and other "yellow" metals found in the trans.

Newer manual transmissions use stamped steel blocker rings with an organic clutch material coating the wear surface. The material looks very much like the material used on automatic transmission clutch plates and bands. The newer synthetic lubes provide the proper coefficient of friction to work with this type of clutch material. But it is so slippery that it will not allow the older brass blocker rings to operate properly.

 

The Pennzoil Syncromesh Transmission fluid with Lucas gear oil additive really helped an old 4 speed that I had.

 

Richmond makes a nice GL4 lube too, hit or miss they have it at the speed shop I use.