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rolland
05-27-2014, 05:37 PM
I have a friend that had spun the bearing on his Jeep axle, he ordered .030 undersize bearings for it. He wants me to turn the shaft and refit the bearings, but I have misplaced my book and need to know what the interference fit is . I think I remember as .0005 to .001 per linear inch for ball bearing.

lakeside53
05-27-2014, 09:51 PM
I'd go to the bearing manf for data. 5 10ths to 1 thou per inch on a steel shaft is LOT for the internal bearing bore. That internal fit will be telegraphed to the ball race, and may damage the bearing.

Also.. Is it supposed to be a "hard" fit, or a "light" fit? Surface finish of the shaft will have a large effect on the actual fit.

Willy
05-27-2014, 11:06 PM
Not sure what axle you are working on other than it being a rear axle in a Jeep.
Is it a Dana 44? I'd have to look up the bearing/axle interference figure, (no access to my manuals at the moment) but if I remember .0015" is not too tight ( I've seen some close to .002"). Double check the bearing fit to make sure as I'm going by memory. The bearing lock ring is a maximum of .005 interference fit.
If it is a 44 or one like it, remember the interference fit of the bearing and lock ring to the axle is the only thing keeping the axle in place.

gambler
05-28-2014, 12:14 AM
as an aside, there are offset bearings available to fix that without machining. (most c-lock style axles)

rolland
05-28-2014, 01:20 AM
gambler
I am only the guy with the lathe, the Jeep owner is in charge of buying the parts he needs for his vehicle. He has not brought me anything yet so the question was based on what he wanted. Things could change when he shows up. I just wanted to have some kinda idea beforehand

Willy
I assumed it was a rear axle. Will know more when he shows up that was what I thought when he mentioned the problem. As I recall the fit has to be correct to keep the axle in place. Further research will follow