NV 3550 conversion driveshaft length

[khumphreys]

I am curious about the rear drive shaft on my 72 bronco. I am also too lazy to go back outside and look under it. Is the rear drive shaft telescopic or is it solid. The reason I am asking is, I have read the tech articles about the NV3550 conversion, and it says that after everything is said and done the drive train is an inch longer but the driveshaft will need no modification and will be perfectly fine. I would like to do this mod and install a 2 or 3 inch suspension lift and know that I would need a shorter shaft for that too. Will both mods make my driveshaft too long?

 

[ogr]

Your rear drive shaft (and front as well) has a slip joint in it. That's why with the NV3550 coversion no driveshaft mod is needed. The slip joints can accommodate and extra inch plus or minus of travel. If you are going to lift your vehicle in conjunction with the trans change then you may very well need to modify the drivelines (front and rear). Plus replace brake lines and steering linkages, etc to accommodate the lift.

 

[trailpsycho]

I am curious about the rear drive shaft on my 72 bronco. I am also too lazy to go back outside and look under it. Is the rear drive shaft telescopic or is it solid. The reason I am asking is, I have read the tech articles about the NV3550 conversion, and it says that after everything is said and done the drive train is an inch longer but the driveshaft will need no modification and will be perfectly fine. I would like to do this mod and install a 2 or 3 inch suspension lift and know that I would need a shorter shaft for that too. Will both mods make my driveshaft too long?

Actually, as you lift the suspension, typically, you will need to lengthen the driveshaft...not shorten it as you mentioned. A 2.5" SL and the NV3550 will fit nicely with your old driveshafts (Fr & R). As mentioned, you will need to replace the frame-to-axle brakelines. As well, with any suspension lift you may need to modify your steering to re-achieve the proper geometry.

 

[DirtDonk]

And, as you'll read here as you go through old posts, having to change the driveshaft length after a lift is NOT a universal issue. Some have to lengthen them, some don't have to do a thing. I have a 3.5" lift and a stock front shaft and virtually stock-length rear.

Paul

 

[rjrobin2002]

You will need an extended rear drive shaft and a stock length front drive shaft. I have a 4" lift and my drive shaft lengths showed that. The NV 3550 is shorter than stock, so you do not need to shorten the front shaft cause the lift pulls the T-case away from the front end. The rear will need extended because the shorter transmision pulls the T-case away from the rear axle and the lift also pulls the T-case away from the rear axle.