Re: 90 wt mineral oil

Posted by JWL On 2011/7/27 16:28:33

I was experiencing gear "crunching" when shifting into third gear (high) in my 47 Clipper Custom with overdrive. It worked better when the overdrive was engaged because of the freewheeling. During the recommissioning of the car I drained the trans and od and refilled them with 140 weight straight mineral oil I bought from an oil distributor. I settled on 140 instead of 90 weight because of central Texas warm weather. I had to buy a 5 gal bucket. It did not help the crunching.

Several months later I installed new rubber bushings in the clutch anti-chatter rod. The clutch chatter all but disappeared, and the transmission shifted so much better. The high gear shift was without any crunching, just a positive move into the gear. Next garage session with this car I am going to drain the mineral oil and refill with 85W-140 GL5 gear oil. The 140 weight is a bit stiff when cold and this is the only time there is a slight crunching. The 85W-140 weight gear oil should fix this problem.

Wow, that story took a long time to tell. Thanks for your patience.

(o{I}o)