How do you rebuild a front axle?

[mikeshoup]

So I just replaced a broken axle on the p/s of my wagon, and now the d/s has a torn boot.

 

Assuming the shaft on my broken axle is fine, how can I rebuild it? Where can I get a new CV Joint? What tools do I need to take everything apart?

 

I know I'll need a new boot, boot clamp, and a CV joint...

[misledxcracker]

I'm also curious about this...

[PoorManzImpreza]

Dissassembly:

 

1 remove half shaft from car

 

2 clean axle shaft

 

3 place in vice with wood lining or equiv.

 

4 remove inboard DOJ (Double Offset Joint) boot clamps

 

5 slide boot down the shaft towards the center or cut it off if not re-using

 

6 using a small flat head screw driver or equiv., remove inner race retaining ring from grove in DOJ housing this is just inside the DOJ housing and prevents the inner race and axle shaft assembly from falling out/being removed from inboard DOJ

 

7 place a cloth around DOJ and remove the DOJ housing from the remainder of the axle shaft assembly and place it big end up on a flat surface. The cloth is to prevent liquified grease and/or worn ball bearings from falling all over the place (them balls can bounce!) usually if the balls drop out it is considered and indication of a worn DOJ

 

8 clean as much grease as possible from the inner race and using an outside snap-ring pliers or equiv. remove the snap ring and slide the inner race from the axle shaft splines. Keep parts organized.

 

9 slide DOJ boot off of axle shaft and disgard or place with other parts preferably in the cloth with the rest of the vile grease if reusing

 

10 Remove boot clamps from Outboard Joint; BJ (Bell Joint) and slide boot off the shaft.

 

11 rotate BJ through its range of motion looking for any binding or any sudden stiffening of the joint. If the grease in the joint pours out it's safe to say the joint will be worn, how much depends on how long it's been opperating in this condition.

 

12 flush all parts with solvent cleaner removing all grease and dirt form the parts

 

13 inspect all balls and races for pitting, gouging rust or any deformation

 

14 remove axle from vice and go find a two foot long 2x4 made of very hard wood or equiv. drill a hole about 2" in from one end on the center line. Slip axle shaft through the hole and retighten in in the vice so the BJ is facing down with the wood resting on it. place other end of 2x4 on something strong so the wood is parallel to the floor. Make sure the vice is very tight

 

15 get BFH (Big you know what Hammer) and strike the 2x4 as close as possible to the BJ side as hard as you can.

 

16 usually one or all of the following will happen: the BJ will be driven off the axle shaft, the 2x4 will break (damn u strong) or the axle shaft will slip in the jaws of the vice.

 

17 Sometimes a sacrificial inner race can be placed on the inboard splines with it's retaining c-clip and that used to prevent the axle shaft from sliding out of the vice, slide the shaft down so the inner race is flush with the vice and readjust whatever you had supporting the other end of the 2x4 so it is level and have at it with the BFH, this has worked for me but it could damage the splines so I don't recommend it.

 

18 If all else fails get your angle grinder and a metal cutting wheel and cut the BJ from the shaft very carefully so you don't damage the axle shaft in any way (I've done this as well)

 

Assembly:

 

1 acquire new outboarb BJ usually comes in a kit with grease, boot clamps retaining ring, axle nut, boot and cotter pin, if your smart you'll toss the grease, boot and clamps in the bin and go buy a new subaru genuine boot and some hose clamps of the correct size to replace the boot clamps. I've used high strength moly fortified grease texaco brand I can recall now lol and I've used sta-lube (CRC) moly fortified grease as well..had horrible results with the grease that comes with the joints and the boots..this is where you get reliability with rebuilding axles and reasonably priced componenets (read cheapish) I normally use GCK outboard joints.

 

2 slide boot onto axle shaft from BJ end with big end of boot face out

 

3 place retaining ring in groove on the axle shaft

 

4 Inject grease inside the splined inner race of the new BJ until it is filled

 

5 press grease into the balls and cage of the BJ

 

6 slide BJ onto axle shaft compressing retaining ring, sometimes you need to give a light tap with BFH to get it to go past the retaining ring. DO NOT hit hard or the BJ will go to far onto the shaft and the retaining ring will miss it's seat in the inner race of the BJ that locks it on the shaft and you'll have $#@ time correcting this

 

7 if you've used enough grease when the BJ slides onto the axle shaft grease will get squeezed passed the balls and cage of the BJ.

 

8 squeeze about 2.5 oz of grease into the boot you slid on the shaft earlier and slide the boot towards the BJ and slide it onto the BJ so it fits nicely in the grove

 

9 make sure the small end is also in its groove on the axle shaft

 

10 burp air out of the boot by place small flat bit screw driver under lip of boot until the pressure is equalized

 

11 remove excess grease and place hose clamps over the retaining areas on the boots and tighten down

 

12 assembly of DOJ is reversal of dissassembly, use new grease and new boot and hose clamps as required..DOJ do ware but not as much as BJ so you might be able to get away with reusing the joint

again if DOJ assembly rotates without corresponding rotation of axle shaft the joint is worn, if balls fall out of the cage when removed the joint is worn..GCK also makes DOJs..

 

13 place newly rebuilt half shaft back into car, repeat as needed..

 

Having said all of that do yourself a favor and head down to your local wrecker, PAP etc and find yourself some used Subaru (NTN) half shafts with good boots and tight joints and repack them with grease and new boots and call it done...

 

HTH,

 

Kaz

[nvexplorer]

That is an awesome write up! I now know more about the axels on my subie than I did even after replacing one. This should be archived or added to the USRM!