drive shaft length adjustment

[Gruffid]

Are drive shafts adjustable without getting them sent to a professional to resize them? For instance, if I need to change my transmission out with one that's 1.5 inches shorter, can I use the same drive shaft, or do I need to get it lengthened professionally?

Thanks,

[DmaxMaverick]

1.5" is quite a bit, relatively. The problem isn't only the spline engagement, but also the sealing surface contact area. Install the shaft, jack up the rear end by the chassis and rotate the shaft (to fully extend the suspension, showing the full extension of the yoke). Measure the actual spline engagement length and inspect the sealing surface area (where the seal contacts the yoke). You may also be able to source a longer yoke, to offset the the needed length (which will also have a new sealing surface).

[Gruffid]

Well, the short term is to get an overdrive unit that bolts in after the transfer case. So, I'm going to need a shorter drive-shaft anyway. However, if/when my 4L80e craps out, I'll replace that with an NV4500, which is (apparently - as I haven't been able to get my hands on one to measure) 1.5" shorter (with the tail housing/transfer case adapter) than the 4L80e.

If that's the case, I can ask the drive-line shop to put a longer yoke in so that I don't have to get a second modification on the driveshaft.

If you have any comments, or constructive criticism on my idea, or need to "set me straight" on expectations, feel free.

Thanks,