I need help on getting the correct Rear Ring and Pinion for my Hummer H3 3.7 X with rear Diff lock,

The research I have done is that the rear Ring is a 8.5 inch with a 4.56 ratio and the front Ring is a 7.5 inch with a 4.56 Ratio for the 3.7 I-5 engine

Unfortunately I ordered the 7.5 inch with the 4.56 Ratio thinking it would fit on my rear diff. BIG Mistake.

So now I realize I need the 8.5 Inch Ring for my rear diff, So am looking to order again but see so many Ratio's [example 4.10 , 3.80 etc] available on the 8.5 inch Ring?

My question is , does the ratio of the gear and pinion change the actual size of the ring and pinion ? as im worried it wont fit and I have another useless part

Any experience and information would really be appreciated?

Also Ive found the part part but it only says for the H3T is there a difference in the ring and pinion between the H3 and the H3T?

Kindest thanks
Johan

 

I5 H3s all have 4:56 ratios, if you already ordered a 4:56 for the front, you will need a 4:56 for the rear. Alphas have 4:10 ratios, same size rings as the I5s.

To answer your question, an 8.5" ring is and 8.5" ring. A ring that size can only squeeze so many teeth on it.

Those other ratios are for other GMs using an 8.5" ring, like S-10 pick ups and Jimmys etc...

 

both gotta be same ratio or you wont go anywhere. 456

 

Ok Great Thanks Very Much ,