I'm having a shop rebuild my 700R4. New servos, shift kit, new bands and clutches.

Do I need new drums as well or can the old ones be machined?

Need advice so I don't make any mistakes.

 

ANY Rebuild should get a new sunshell. ($50 to $65 shipped) get the beast.
a true beast sunshell will have the patent # on the unit. anything with out it is a sub stand copy!(junk)

just good parts for a 700R4 will run $2300 to 2400. just for hard parts.
it will hold up to 700+ hp

but for a good street redo $300 in parts to put it together is fine

ANY sunshell without this mark is a cheap knock off copy!
the real thing is cheap at $50 to $65. so dont get ripped off...when sombody tells you..it's the same thing...lol it's not!


B&M makes a kit that comes with all the standard clutches&steels. and seals. it also comes with a killer shift kit that makes/turns the valve body into a manual automatic valve body.. you can let it do all the shifting..or do it your self. and hold it in geat till hell freezes over!.. works fantastic. i think i paid $200 for the kit years ago... good luck on you rebuild

 

You do not need new drums unless they're damaged in some way. It's perfectly fine to re-use what you have.

I don't know what you'd machine on either the input or reverse input drum unless you're talking about the surface of the reverse input drum where the 2-4 band rides. If this surface is damaged enough to need machining, it would be better to just replace it.

The shop that's doing the rebuild should be able to tell if the drums are in good shape to be re-used.

 

Just straight edge the drum to make sure its flat and the beast sunshell is not needed the new hardened gm shell is just as strong and is balanced,

 

Oh and the beast shell is not balanced so you will fell some vibration

 

A just fyi. I have been running the beast sun shell in all my 700r4's and I have no vibrations in any of the cars. Must be an enigma....but then again my Detroit lockers make no noise .and are as smooth as glass...just me I guess....

but would love to see some pics of bal shells and un bal shells.
there is a reason it has a patent #...
candy man...candy man..candy man....lol
another myth

Nexed it will be.. your planet gears need to be balanced..your ring and pinion needs to be balanced or you will have a vibration... Where do guys come up with this s***