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So I've currently got 4:88s in the rear which is lower than most, believe me when I say I want a beefier diff, I just don't get how the rear end shop came up with that price. It's cutting the tubes, rewelding them and cutting new splines on the axles.

 

The H-190 ring is almost 7.5" diameter. The more gears you try to cut on it the thinner they are. The thinner the weaker.

 

A 4.875 has 39 teeth that are about .6" wide. On a 9" differential they would be .725" wide

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Put it this way, the open diff will break inside way before the case does. They also come in ratios 3.364, 3.545, 3.70, 3.90, 4.11, 4.375, 4.625, 4.875

 

The aluminum case can be 4.875 or 4.375 if from L520 or PL521.

Steel... 3.364 through 4.625 were in 720s

Steel... 4.11 through 4.625 were found in the 620

 

All truck diffs have the 29 spline side gears that will take the truck axles. Many of the 2wd 4 cylinder D-21 trucks also use this diff.

I'm sure an 8th will make a substantial difference to the strength of the gears. So if I follow correctly if I were to use a higher ratio gear set the teeth would be thicker?
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On the same diameter differential the fewer teeth the thicker they would be. The H-190 4.875 would be 39 tooth. The 3.889 have only 35 teeth on the ring gear.

 

The 39 tooth would have gears that are 0.602" wide

The 35 tooth would have gears that are 0.671" wide.

 

Not much wider but going to a 9" differential the same number of teeth would be 0.725 wide.

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image_zpsk8fu23um.jpg

Resolved my rear brake issue, i bought the Italian made cylinders which I hear aren't the best but they do come with y's. Maybe in a couple years when they crap out I'll get the Isuzu rear set up.

 

where is your e brake strut?  just wondering because I have tried running without,and learned that it keeps the wheel cylinders from sitting under spring tension when not in use. also made a huge difference in adjustment.  Not sure If you can get them to adjust up without it but I figured I would let you know my experience with them.

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I didnt try to see if they would adjust without the strut.  I knew putting them back in would reverse the problem so I just did that.  The lever has to remain to keep the strut in proper location.  Worse case you wont be able to adjust them all the way to spec and they will take a couple pumps to get them in contact with drum.  If you are still in need of the struts when I swap in some Beef I can give you my old ones.

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Thank you dude. I have the same problem. two of my sockets are toasted.

I'm just happy to pass the info along! Only thing you gotta do if you want them really secure is make a baby notch in the bulb housing fingers where they click into the plastic. But the housings were like 2.99! Screamin deal

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