[mh1984]

Im in a delima. I have a 94 c1500 that has a 4l60e and im wanting to instal an nv3500 built in the year range 88-90. What year do I need to get a flywheel from in order to make this transmission work? Ive already ordered a brand new clutch kit for this transmission. I have no idea of tooth count on the flexplate nor any idea of the tooth count on rhe statee. I desperately need to get my truck rolling again. HELP PLEASE !!!!!!!!!!

[techinspector1]

Is this a Gen I or Gen II motor? I know little or nothing about the II and III motors, but will try to help. I'm told the NV3500 has an integral bellhousing that will bolt up to a SB, so I guess the only thing you'd need to know is whether it is internally balanced with a neutral flywheel or externally balanced with a weight on the flywheel. One piece seal or two piece seal would make a difference also. LT1 would have a 153 tooth ring gear I think.

[mh1984]

The engine is a 2nd gen i think. It has an internal ballance shaft and is a vortec. The rear oil seal is a one piece. Ive read that a 350 flywheel isnt a good thing to use due to the uniqe ballance of the 4.3 . My clutch kit came in today and I ordered it for a 88-90 nv3500 . The nv3500 i have is the first design and the casing is a two piece cast aluminum. The bellhusing is integeral. The nv3500 had a few design changes over the years. New venture was a partnership between chrysler and gm. The transmissions had similar designs and internal workings but one would not cross over to the other due to bellhousing bolt patterns. Im not sure if the internals cold be swaped over though.

[bondo]

Originally Posted by mh1984

The engine is a 2nd gen i think. It has an internal ballance shaft and is a vortec. The rear oil seal is a one piece. Ive read that a 350 flywheel isnt a good thing to use due to the uniqe ballance of the 4.3 . My clutch kit came in today and I ordered it for a 88-90 nv3500 . The nv3500 i have is the first design and the casing is a two piece cast aluminum. The bellhusing is integeral. The nv3500 had a few design changes over the years. New venture was a partnership between chrysler and gm. The transmissions had similar designs and internal workings but one would not cross over to the other due to bellhousing bolt patterns. Im not sure if the internals cold be swaped over though.

Ayuh,.... Is the starter a straight, or staggered pattern,..??
Is the block drilled for Both patterns,..??
What diameter is the clutch,..??

A '94 is Vortec in name only, as the Vortec heads weren't Intro'd till '96...

My Guess is ya need a 14" flywheel, for a '94, 'n Up 4.3l motor...

[mh1984]

The starter is straight. It only is drilled with one bellhousing patern. It currently has a 4L60E behind it. Im rebuilding it later on to make it last with a level 4 kit. I think the new clutch disk is 11 inches ill have to measure it to be sure. Haa anybody ever done this swap before from auto to manual? All I lack is the flywheel.

[mh1984]

Thanks to those who helped to aswer my questions. I have found a flywheel for my conversion to manual. I called advances adaptors and it turns out that all GM truck flywheels from 86 to 98 are the same.