Part # for correct front U joints at wheels

[Toro]

I need some help determining the correct front U joints at the wheels for a factory Dana 44 on my 72 Blazer. Using RockAuto search, there are three bearing cap sizes that show, 1.188, 1.125, and 1.062. These all show as Dana 44 front axle at wheel with inside clips, which is correct, but I'm not sure why there are three different sizes. If anyone has replaced theirs, do you remember a part number that worked? Thanks, Jon.

[kwmech]

You'll have to measure the outside diameter of the u-joint cap to get your answer

[Toro]

I understand that would be one way to find out, but does that mean there are really three sizes for the same part? I'm would like to have parts on hand before it's all removed.

Anyone else replaced these and remember which ones are correct?

[litebulblsc]

1972 had a larger size then previous years. I am not sure what that size us though. But worth mentioning in case someone with an earlier year tells you what size theirs are.

[Toro]

Originally Posted by litebulblsc

1972 had a larger size then previous years. I am not sure what that size us though. But worth mentioning in case someone with an earlier year tells you what size theirs are.

Thanks. I think that's what might be tripping me up. Looks like the width across from cap to cap at 2.188" is consistent. It's the width of the actual cap I'm not sure of.

[Toro]

From TorqueKing 4x4:

GM used at least three different axle shaft configurations for 1969-1972 Dana 44 front axles. 1969 Blazer inner axle shafts are 1" shorter than 1970-1972 axles. The outer axle shaft for 1969-1970 drum brake axles are 1/10" shorter than those used on 1971-1972 disc brake axles. In mid-year 1972, the axle u-joint size was increased from 1310WJ series (1-1/16" cups) to 1350WJ series (1-3/16" cups) although the lengths remained the same. General Motors used an small Spicer 1310WJ series axle universal joint with tiny 1-1/16" diameter u-joint cups for the 1969 to 1972 on Dana 44 open knuckle front axles. The physical dimensions of this series of axle joint means is marginal for full size truck applications which is why it was replaced by Spicer 1350WJ series medium size axle u-joints with 1-3/16" cups during the 1972 model year

So that explains why I've been seeing two separate ones listed for 1972 model year. I'm not sure when "mid-year" it was changed. My Blazer build date is early, September 1971. I guess I'll be measuring tonight to see which one it is. I also wondered if there is a stamp on the tube that might be different before and after the change.

[H8tulooze1]

Originally Posted by Toro

I need some help determining the correct front U joints at the wheels for a factory Dana 44 on my 72 Blazer. Using RockAuto search, there are three bearing cap sizes that show, 1.188, 1.125, and 1.062. These all show as Dana 44 front axle at wheel with inside clips, which is correct, but I'm not sure why there are three different sizes. If anyone has replaced theirs, do you remember a part number that worked? Thanks, Jon.

Im replacing mine now and I got the 1.062 ones. I had to measure the cup size, first Napa got me the bigger ones, didnt fit.