I have an 06 X and just replaced both front CV joints because I'm getting what seems like shuddering when I brake. I didn't realize when I replaced the front passenger CV axle that it seems sloppy in the diff end, and also when coasting after breaking I'm hearing a very metallic pinging/ticking sound, so I'm thinking the bearing is shot in the diff. The FSM says to remove the suspension member which allows you to remove the diff without jacking up the engine. Did you guys try this or is that more of a PITA than lifting the motor? I may just pay a trusted mechanic I know to do it but not sure if he's ever worked on a G35 before, but it's probably not much different than all the 4x4 half tons he works on around here....lol.

 

Are you sure the tinking sound isn't coming from the front u-joint? That's the sound I was getting when my u-joint was almost completely failed like several others you see on this forum. Those guys had them fail completely and often break the diff housing. My u-joint was so bad you could rotate it and move it up and down by hand. There's a thread with pics of mine somewhere here.

 

But it only tinks after braking and then coasting. I only get vibration under heavier braking, like every stop light. If it was the shaft wouldn't that be constant?

 

Dude, I totally owe you a beer. I reached under the car and just moved the driveshaft with my fingers...loose as **** and making the pinging sound. I hope that's all I need, hate to have to replace the side bearings in the diff, much bigger job. How hard is it to do without a hoist? I might just pay someone to do it.

 

yeah we all owe beers to the guys who wrote about their broken diffs from failed u-joints. i can't explain why the vibration and noise is the way it is.... but that's how mine sounded too.

i paid somebody to do mine when i couldn't get my cats out in order to drop the driveshaft. I forget how much i paid but it wasn't outrageous at my local indy. i bought a driveshaft from rockauto that has a serviceable u-joint and they put it in. good luck.

 

I saw a youtube vid of a guy that got it out without removing the cats, just dropped the steering rack and managed to get it out...I was hoping to do the same. Did you have aftermarket ones?

 

I'm putting new driveshaft back in today. Damn near same thing happened with u joint, but fortunately did not crack differential case in process. Sealed up wear hole with liquid metal. Cat bolts require patience and 2 feet of extention. A breaker bar and impact took care of it. Sprayed bolts with penetrant let sit 24hrs, hit em again and a couple hours later had cat dropped. I'm in PA. It just takes patience and technique.

 

So you had to remove your cats for sure then? Couldn't work the driveshaft out and back in?

 

Yes, there is not enough room. Either drop cat or possibly rack and pinion as someone else mentioned.
you also have to take mount off 2 stainless lines to be able get the driveshaft out and back in. With 4 brackets removed, there is barely enough play to force them out of the way.
on the tail end there is also a cross member and the splined end of driveshaft is about 3" long. I did not remove the cross member.as I didn't see much if any advantage to doing so

 

Looks like I have a worn side bearing on the passenger side of the diff..getting a whine at higher speeds and there is play at the diff end of the passenger side cv shaft. I suppose I'm going to have to drop the diff to fix this correct?

 

I have my 05' back in the garage after changing the front diff I still had a bad oil leak that couldn't be seen so I am tearing it apart again. When the driveshaft let loose originally it destroyed the front diff and beat the upper aluminum oil pan taking a few chunks out of the edge. What happened was that the diff locked up and was so violent that it cracked the upper aluminum pan where the diff supports bolts on to. One of the bolt mounting boss actually broke out after I removed the upper pan and the hole was so big I could put my thumb knuckle in it, also had a crack all the way up to the engine block. Long story short don't ignore driveshaft noises like the last owner of this car did

Anyway I found this time around that removing the suspension and subframe (while the engine and tranny are on jackstands) is actually a lot easier than I thought. I had the whole front end apart and the oil pans off in about 5 hours. With all of that crap out of the way the front diff is cake to get in and out. One hint for anyone changing their diff is to buy the inner and outter axle seals and also the big oring so you don't have gear oil leaks. The part numbers are in one of my threads if you don't feel like part searching for hours

Don't get me wrong the front diff can be changed with just dropping the subframe 3-4 inches but you will fight it out and in and can possibly damage the seals like I did the first time. Oh yeah I removed the passenger cat, y pipe and transmission cross support to change my first driveshaft.

 

Ok, so if I'm just removing the diff, do I need to remove the passenger cat and y-pipe? I'm worried it's fused on there.

 

Also, when removing the diff, asside from the side bearings and seals and orings anything else recommended to replace while it's out?

 

To remove the diff.
You will have to remove the Y pipe, Passenger cat, remove transmission cross member, remove front driveshaft, remove driver and passenger side spindle and axles, remove intermediate axle (goes through oil pan into the diff), Passenger motor mount and bracket, at least drop the engine subframe 3-4", drop the steering rack (can leave lines attached). I'm not going to lie it's a lot of work and a little rough fishing it out and in with the engine subframe in the way. I will probably pull the subframe out from now on since it makes the job so much easier and less chance to screw seals up.

About your diff bearings. If you are changing the diff bearings I hope you know how to use gear marking compound and setting gear lash because if you get it together wrong it is going to sound like an airplane when rolling. I would just replace it with a low mileage unit. My diff was $150 shipped and had under 100k miles. It looked brand new inside. Just make sure to get the 03-06 G35x diff because the 07 up,G37, and suv's have a different ratio.

 

Yeah I already thought of doing that just to make things easier. I'm debating having the shop I use (not scumbags) do the work and that would save them time just swapping it out. Just not sure how much labour they would charge for this job. Anyone know what the shop rate would be for this time wise? I don't have a hoist and the prospect of doing this on a garage floor makes me cringe a bit. I have had the suspension apart and back together many times but at some point it's just worth it to pay someone to do it.