NP241 driveshaft

[lowrodderchev]

hey guys I doing a LS swap in my 75 blazer and running a NP2421 case. I have a 4 inch lift so my question is does anyone know if I can get away with running a stock 87 blazer driveshaft? I'm hunting for one and having no luck. hate to find it and realize it wont work. or does anyone have suggestions for a alternative driveshaft? thank you

[lowrodderchev]

or can I just adapt the np241 yolk to my 203 driveline?

[obijuan]

Doubt it and no. You didn't say which trans you're using, and that could change everything. What I would do is use a slip yoke from any 1985 and older 4x4 3/4 or 1 ton. That will be 1350 and will hold up very well to the power. Then whichever rear axle upgrade that yoke to a 1350 to match. Make a driveshaft to fit.

[lowrodderchev]

I'm using the 4L60E. Found a guy with a long bed driveline that I could get would just need to cut it

[andrewmp6]

Call a local big diesel shop most can custom make driveshafts for anything.

[special-K]

Which driveshaft?

[lowrodderchev]

The rear. I read on another site were someone just added the front yoke to his 205 driveshaft but guessing from a previous response that's a big no no

[lowrodderchev]

Has anyone used the driveshaft superstore? They have a slip eliminator that's looks interesting

[andrewmp6]

Take a look at http://www.offroadltd.com/K5Products.htm

[lowrodderchev]

Thinking about trying one of these out anybody use them.before?

[obijuan]

Good luck getting that centered. Generally regarded as the worst option.

Jb conversions SYE kit is excellent and is a good price for the quality of what you get.

[lowrodderchev]

One I looked at is $400 ouch lol I started a build thread for it. Someone suggested just trying it as is to see if its ok. I've read a slip yoke with a 4 inch lift could have issues maybe I'll be ok

[andrewmp6]

Just depends how far the slip yoke pulls out once you lift it.It could cause vibrations depending on driveline angels,Or worse case lifting it really makes the shaft shorter then you need and you floor it and the driveshaft slip yoke just slides right out lol.But at 4 inches i believe you should be ok and maybe just have vibrations any higher then you got real problems.If you get vibrations you could do a t case drop its cheap easy but more a bandaid tell you can get a sye and new rear driveshaft.

[First c10]

On my lwb 4" lift ls swap with a np241 I used a 31 spline slip yoke from a th400 and had a custom driveline made 300$ complete just had to bolt in.

[lowrodderchev]

Got ahold of this 3/4 ton driveline going to have someone shorten it. From 1/2 to 3/4 driveline I should be good right?

[andrewmp6]

Is the u joint on the axle side the same size?If not you can run a a conversion one.

[lowrodderchev]

Ok crap didn't think about that one. Most likely isn't were do they sell conversions? I'm new to 4 wheel stuff but learning rapidly lol

[andrewmp6]

Measure the u joint cap on both driveshafts this chart says which size is what size http://www.driveshaftspecialist.com/...D%20Guide.html the conversion ones any auto part store has just say which two size series u joints you need.

[lowrodderchev]

There's no downside to running the bigger driveline right?

[lowrodderchev]

full of questions hopefully you guys can help me. behind the screw cap on the front driveshaft there was a plastic ring. most of it was gone. I'm assuming it stop the driveline from sliding out. does anyone know what that parts called?

[First c10]

http://www.dennysdriveshaft.com/c565...and_seals.html

This should get you what you need.

[lowrodderchev]

Bingo thank you helps alot

[andrewmp6]

Yeah theres really no downside to a bigger driveshaft,If you have to run a conversion u joint that could be the weak point if you get on it hard stuck,But most off roaders carry spare u joints and things like that just in case.If its just a normal 4x4 then you have nothing to worry about really.

[lowrodderchev]

Had no luck with Denny's driveshaft for the seal that sits between the screw cap and the driveshaft. Any suggestions? Buddy of mine told me to just slide a o ring in there and call it a day. I'm able to slide it apart without unscrewing the cap is that normal?

[First c10]

Not sure why the Denny's parts wont work for you..
What is the spline count? 32?
The Spline diameter? 1-3/8"?
The overall cap diameter? 1.779"?
based on the precise measuring device pictures! it looks like 1.779" would work. Denny's part number D2N.

D2N Dust Cap