1971 Commercial Chassis Rear Wheel Bearings, Seals and Retaining Rings

[nightcrawler]

Hi guys, I'm looking for some help with the replacement of the rear wheel bearing set up 1971 Commercial Chassis.

It all started about a year ago when the passenger rear wheel bearing collapsed, when I took it apart I found out that the bearing was not an original but an after market version that I have heard being called the green bearing which has the wheel seal built in, I didn't like the idea of this bearing as it is a ball bearing, the original was a taper bearing, anyway the only replacement I could find at that time was a green bearing, I fitted this BUT 420 miles later the half shaft pulled out of the differential, when I took it apart the retainer and bearing had come off the shaft allowing the whole half shaft brake hub and wheel to pull out of the differential.

I measured the retainer that had pulled off and found out that it was exactly the same size as the shaft, so after more searching I found another aftermarket bearing this was a straight roller bearing with a separate seal and a retainer with a 3 thou interference fit which took over 7 ton of pressure to press on, after 300 miles I had an oil leak, on looking I found out that the retainer had slipped by 2mm, upon checking I found that the overall width of bearing and seal was less than the original by 1.75mm so I had a spacer made up and pressed the retainer back into position, taking another 7 ton of pressure to do this, after another 378 miles I checked and there was no oil leaks but after raising the car and checking for free play I have 2mm of play on the retainer AGAIN!!!

Does anyone know what interference fit I should have on the retainer? as 3 thou obviously isn't enough.

I have now found a bearing that is an exact replica of the original taper bearing but I cannot find a suitable seal to go with this bearing, Does anyone know if I can get an original seal from anywhere or if someone makes an aftermarket version which is an exact replica of the original?

Hoping someone can help me.

Thanks in advance

[The Tassie Devil(le)]

In the past, I have found differences in the collars that come with bearings.   Some are press-on types, and the rest are of the heat-up and let cool ones.

The press-on ones are labeled "do not heat" and all the others without labels are the heat-up variety.

Never press on a heat-up one as they will never hold.

Bruce.

PS.   Not sure what the interference fit measurement is, but some engineer here should.

[nightcrawler]

Hi Bruce thanks for that!!!

Does anybody know what interference fit I should have on the retaining ring to hold the bearing in place on the half shaft??

Thanks

[nightcrawler]

Ok if no one knows the interference fit for the commercial chassis, does anybody know the interference fit for a standard Caddy? just so I got some figures to give me an idea of what I need.

[The Tassie Devil(le)]

Me thinks you are going to have to rely on a good machinist to make you up one, with at least a 10 Ton sideways clamping pressure.

The heat-up ones are mild steel, and grip really tight when they cool down, and have to be removed by using a Cold Chisel to spread the band.

But, if you have the dimensions of the axle diameter where it fits, a good Bearing Shop will be able to get you the correct one as well.

Bruce.

[nightcrawler]

Yeah I know a good machinist in work, but I need dimensions for him to work off, so I can get one made that will take 10 ton of pressure.

All the engineering bearing places which we use in work have all said that they will not commit themselves to give dimensions as automotive bearings have different forces to what they are use to dealing with, and I cant find any specialist automotive bearing companies in the UK, the only European vehicle which uses that sort of size bearing are 4 x 4's but none of the 4 x 4 places have even bothered replying!!!

Thanks anyway