Big bearing 9" conversion question.

[nickeboy]

I upgrade to a big bearing axle from a 1966 small bearing 9". I have found out that my old driveshaft (ujoint) will not fit. I'm trying to decide what the best upgrade would be. I upgraded to extreme drive shaft from wild horses a few years ago. So what's the best way to fix this?

 

[nickeboy]

Should I just change the yoke on the 9"?

 

[thegreatjustino]

Change the whole third member back to the old one.

 

[nickeboy]

That sounds difficult. Any better advice

 

[jperry1290]

Why did you upgraded to the BB? What use will you have for the rig? I built a BB housing with new 31spline shafts, gears, and a Yukon locker (which has been awesome). I also upgraded to the bigger drum brakes. I think it was close to $1400 to build it all with having a guy set up the gears.

 

[dukeflr]

Why wont the U-joint fit? The caps are too small or they are a larger dia than the new third member yoke? What did you gain by using the new third member? Different gear ratio, better locker, 31 spline?

 

[nickeboy]

Yes, I upgraded. I got a BB9" with disc brakes 4:54 gears and a locker. It is also a full floater and a currie rear end. With the deal I got a d44 to match.

 

[nickeboy]

http://classicbroncos.com/forums/showthread.php?t=253922&highlight=Dana+44

 

[nickeboy]

The yoke on the BB is bigger. I'm assuming it is the Borg. Im also assuming that I had the spicer on my old 9"

 

[horseshoe]

Driveshaft

I think I would have someone cut & replace the end of your driveshaft to accept required u-joint , either locally or shipped back to place of purchase .

 

[snipes243]

Sounds like the yoke on the BB is a 1350 while the stock bronco drive shafts are 1310 joints. Just go to oreiliys and ask for a 1350 to 1310 conversion joint I believe the
Dana spicer part number is 5-460X 1310 - 1350
NAPA part number 348


Here's how to check what joint you have.
http://www.actionmachineinc.com/ujointmeasuringguide.aspx

 

[Toddpole]

Pull the yoke off the rear end. Take it and the driveshaft to a driveshaft shop. They can help you decide the best route.
FWIW-I think you probably have a 1310 u-joint on the shaft and a 1330 of 1350 yoke on the rear end.

 

[nickeboy]

Thank you guys. I was thinking the same thing. I will pull them off and head down to the driveline shop.

 

[SteveL]

I would hesitate to pull the yoke from the 3rd member. If you don't get the preload right or change the pinion depth putting it back on it will grenade the rear end.

 

[dukeflr]

Do not pull that yoke! You or someone else will have to reset the preload and verify the depth if you pull it. Just do what snipes suggested. Go buy a 1310/1350 combo joint or have the driveshaft shop weld a 1350 end on and rebalance your drive shaft. These are really your only two easy options.

 

[SteveL]

If you go with the combo u-joint buy a spare. They can be hard to find in a pinch.

 

[nickeboy]

I already Pulled it!!! JK i am going to go with a combo joint for now and will have my fab guys look at it once its back on the road.

 

[SteveL]

Make sure the specs are right on the 3rd member. I had a guy do mine wrong and a week later it locked up doing about 50 down the highway. That was fun. Had to buy new gears, carrier and install kit.. guess I didn't get such a deal going with the cheaper guy