Engine/Transmission (1998.5 - 2002) Input Shaft horsepower

[Dieselrod]

At what horsepower did you break your input shaft on a 47RE?

The reason I'm asking is I'm ready for some more power and I am wondering how high I can go before upgrading to the expensive billet shaft.

Thanks

 

[01smokinram]

Input shaft

I thinking about 500 is about what it can stand but it has been broken with less than that. It's according to how you launch out of the hole and the weight behind you. I could be wrong,maybe some one else can chime in and correct me if i'm wrong.

 

[Jetpilot]

Normally its the locked to locked shifts (mystery switch) that kills the input shaft. Now the output shaft is a whole different story. That one has been known to break under stock HP. A new super output shaft will be available soon from TDR member Opz01.



Doug

 

[Motorhead]

When at DTT last month to get my trans done, Bill told me about the bilett input shaft that they use. He showed me a broken one and said that if you use an exhaust brake that it is wise to have the stronger input shaft for that reason alone. He told me that the twisting of the shaft BOTH ways makes them more susceptable to breakage.

I put the bilett shaft in for GOOD insurance and I am planning to put an exhaust brake in also.

 

[fox]

Bill says the stock motor has broken a few.

Since I am at maybe 350hp now and Really need a tighter converter, I will do it all very soon.

That is, 89 converter, upgraded front clutch, and billet shaft andhub.

The valve body has been improved and will do more to it next time it comes down.

I am sure the boat is due to be put on land.

I promise to not go higher in power,------------------------------!







Have you seen the topics on the UFMS and the guy they calll Piers??



HA---------------HA-----------!!!!!!!

 

[Strick-9]

2001 and 2002 Dodge PCMs allow a locked to locked shift under light throttle from 3rd to 4th. I've seen a broken shaft on a stock motor from this.



Another big cause of broken shafts are large RPM drops into lockup from poor fluid coupling.



Personally, I've broken two input shafts because I wanted to put off buying the billet parts.



The first one broke at about 280 HP, but I was forcing my transmission to shift with the converter locked. Stock transmission with a VB.



The second one broke at about the 400 HP level for no apparent reason. No locked shifts, just cruising down the highway. (Complete DTT transmission)



Once you see a few broken input shafts you'll see the problem. Several of them have casting flaws or 'air pockets' in the material making them weaker. There's no way of telling if you have one with problems or not unless you do some ultrasonic testing on it or something similar. Using the factory parts is a gamble at best.



Luckily for me, both of mine broke close to home and I was able to repair it myself. If I had broken somewhere on a road trip and had to pay someone to repair it, wrecker fees, etc. , the cost would quickly run over the price of the billet shaft. I consider myself lucky.



-Chris