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Transmissions and Rear Ends Three on the tree or four in the floor? Shift it all here.

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Old May 17th, 2020, 09:09 PM
mobrien699 mobrien699 is offline
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Default SM420 Rebuild Question

Purchased the master rebuild kit from Novak for my ‘66 SM420. All components from the kit are installed per the instructions provided. All is well with the rebuild until I reinstall the clutch gear assembly (input shaft). As soon as the clutch gear assembly is seated, the entire transmission locks up and will not go into neutral. What am I overlooking???

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Old May 18th, 2020, 01:34 AM
tbucketnut tbucketnut is offline
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Default Re: SM420 Rebuild Question

So are you saying when you seat the clutch gear the main shaft and counter shafts will not turn, is this with the top cover off? Best to call me when you get a chance. I'll pm you my number. Steve
Steve Stock
Gig Harbor, Wa

1953 Chevrolet 3100
261 cu inch, SM420
Finished Cab off restoration

1964 GMC 1000
305 V6, SM 420
Restoration is now started, still looking for an oldsmobile style power steering pump
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