Allison stock shafts

[Kramer]

There's gotta be a thread on this somewhere, but I can't find anything. Does anyone know the limits of the stock input, intermediate, and output shafts? The truck is a 2007 LBZ.

If there's already a thread on this could someone just post a link?

Thanks

 

[JoshH]

In my opinion, there's really no good answer for this. I've seen stock inputs break behind less than 500 hp to the ground and live behind 1000.

 

[Kramer]

That's what I've been hearing, but haven't heard much. I'll hopefully be around 825/1600 when I get my motor back in next week, and I'm just wondering if I should upgrade anything else while it's out.

Thanks for the reply

 

[Chevy1925]

In my opinion, there's really no good answer for this. I've seen stock inputs break behind less than 500 hp to the ground and live behind 1000.

x2

 

[Mike L.]

If you run the truck hard, put them in. I agree with Josh.

 

[Kramer]

Thanks guys. I'll see if they will fit in the budget, but if not I guess I won't worry about it too much. Seems like most people aren't too concerned about them.

 

[PACougar]

Seems odd for you to have a built engine and transmission but not put billet shafts in. Like they said above it's a crapshoot, but for your power goals I wouldn't withhold them. Also considering your own advice, these are cheaper than most turbos and way less headache to deal with while apart then if they break.

 

[x MadMAX DIESEL]

Something like that I would chance it with the stock shafts! I've been over mid 800 on stock shafts, even ran stock flexplate at mid 700s. Unless you cant do the work on your own I wouldnt be throwing money at it in a "diesel priced industry" in it wont cause catisrophic failure! But I'm just voicing my opinion from a laptop in kentucky. Other guys in this thread have seen alot more. But what little I've seen, I'd do it again to save some money for family

 

[gtmax]

Bad thing about not going with billet shafts is when you break a stock shaft you'll know you should have gone with the billets. Depending on the abuse you throw at your truck I'd say over 650/700 hp you should go with the billets, but if you don't agree, your transmission will tell you.

Agree that these pieces are too much $$$$$

 

[RPM Motorsports]

If your doing the work yourself, I bet you can't break enough stock shafts to equal the price of two billet pieces.

 

[PACougar]

If your doing the work yourself, I bet you can't break enough stock shafts to equal the price of two billet pieces.

True Russ, but that's only if you don't value your time

 

[S Phinney]

Billet input would be worth it at your power levels. You should need a billet intermediate shafts at all. They rarely break. Next step would be c3 and p2 billet items and output shafts. You can run up a high dollar tranny pretty quickly.

 

[Kramer]

Seems odd for you to have a built engine and transmission but not put billet shafts in. Like they said above it's a crapshoot, but for your power goals I wouldn't withhold them. Also considering your own advice, these are cheaper than most turbos and way less headache to deal with while apart then if they break.

That is true. I've already put almost 13k into this though, and funds are running low. I'm just wondering if they will hold, or if I'd blow one apart within a few miles after starting it up. About the turbo thing, who puts a stock turbo on a built motor? Seems like these shafts will hold up depending on how it's driven. Putting a stock turbo on a built motor is impressive though. Might as well leave the emissions system in tact and slap the stock exhaust on her as well.

Billet input would be worth it at your power levels. You should need a billet intermediate shafts at all. They rarely break. Next step would be c3 and p2 billet items and output shafts. You can run up a high dollar tranny pretty quickly.

That's what I'm trying to avoid. I'd like it to hold, but I don't want to buy billet everything just because they make it. Maybe a billet input shaft for now wouldn't be a bad idea, then billet output in a couple years when I refresh the transmission?

 

[Mike L.]

Sometimes the broken tip of an input shaft won't come out and will require another converter.

 

[Kramer]

Sometimes the broken tip of an input shaft won't come out and will require another converter.

That sure would suck. Looks like I'll be doing atleast a billet input shaft.

Thanks guys.