8&3/4 gears installation kit advice needed

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Rapid Robert

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have 741 pumpkin. want to install some 3:91's into it. what installation kit do I purchase to give to the shop doing the install? thank you for your time. RR
 
Just a gear change? No current issues with chuck? You could get away with pinion bearing, shims and pinion seal but Kits aren't much, but I do see two different carrier bearing sizes. Not sure how to determine which you have? Maybe housing #??? Possibly axle or pinion spline count? Hopefully someone will assist.
More Information for MOTIVE GEAR R875RM
More Information for MOTIVE GEAR R875RMA
 
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I put a used set of 323 gears in my 741 last year. I just used the shims that were in it. Pinion depth was good no extra shims needed. Put a new pinion bearing and seal. Not to say you would be so lucky.
 
before you order your bearing install kit you have to determine which carrier bearings you have they will be either LM104949 cone / LM104912 race or the earlier bearing 25590 cone /25520 race ,, the O.D. of these two bearings are the same the I.D. is different ,, then find the proper kit to fit your application. Summit ,, Jegs ,, Dr Diff ,, Randys Ring and Pinion or Quick Performance in Iowa probably has the best price
 
the ring/pinion I will have installed in the carrier are on the way. do I need to measure this pinion or pull the highway gears out of the 741 pumpkin & measure its pinion? EDIT I had ordered a 741 installation kit on Ebay & I cancelled it. didn't know there were 2 varieties
 
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The pinion bearings are the same no matter which ratio gears you install in a 741 case.. They are based on the case "741" that gives you a 1 3/8" pinion diameter. The Bearing notes above are indicating which type of carrier you are using. If carrier is already setup and carrier bearings are good, they do not need replaced again to swap ring and pinion. Just buy pinion bearings, races, and pinion seal.
 
If your carrier is the open type or u have the cone type unit then u need the LM104949 and the LM104912. Clutch type uses the 25590 and 25520 cup and bearing. Kim
 
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