WHY O WHY?? REAR DIFFERENTIAL DAMAGED

[20BELLO]

Ok so Im cruising along when a truck stops in front of me, I hit the throttle and sped around him but when I did I heard a loud thump, the wheels locked and it felt like I ran over something and was dragging it. I managed to pull over to the side of the road. looked under the car and I could see nothing hanging down or stuck. Started the car again and could hear this atrocious grinding noise, put it in Drive and the car would not move. I immediately thought it was the transmission.

after towing it home and further inspection i discovered that the rear differential securing bold had snapped off causing the rear differential to hang down. The rubber piece on the drive shaft completely blew off exposing grease……

for the life of me i can't understand why the securing method to the sub frame was not engineered better than one bolt holding it on through the housing bushings!

Now I have been doing research for the last 24hrs trying to see the best way to go about repairs. I am mechanically inclined but would probably take it to a friends shop. The problem im having is actually finding a rear differential for an 06 M45 sport. ITs so hard to find parts for this car.

[ezb57e]

I would try to save the original one unless there is more wrong.
I would try to get the end of that broken stud out of the diff case, and use a bolt on reassembly if possible. I cant remember if space was a problem here.
From the rust, it looks like it was never quite tight and had movement, eventually shearing off the stud.
The rubber mount looks OK from what I can see.
Did you mean the front driveshaft, or one that goes out to a wheel had a boot come off?

[06M4.5]

G37 rear will wake up your M

[EniGmA1987]

The mounting for the rear differential is to the rear subframe, it should be pretty strong. Never heard of anyone with an issue like this before, so Id suspect a defect in the construction of the bolt. You can get new bushings from various places, Energy Suspension sells some. You may be able to buy the bolt from a local hardware store.

If you get a new differential, the M35 and M45 are different. However, you CAN mount an M35 or a G37 differential with just a little bit of work onto an M45. Though if you use one of these other differentials then you also need new axles too as the size, bolt pattern, and spline count dont match up. If you go with a G37s rear differential you can get about 10% faster acceleration just from the differential swap due to the gearing change.

[20BELLO]

I would try to save the original one unless there is more wrong.
I would try to get the end of that broken stud out of the diff case, and use a bolt on reassembly if possible. I cant remember if space was a problem here.
From the rust, it looks like it was never quite tight and had movement, eventually shearing off the stud.
The rubber mount looks OK from what I can see.
Did you mean the front driveshaft, or one that goes out to a wheel had a boot come off?

I meant the rear drive shaft. it wasnt a rubber piece it was a plastic or metal cover piece that shredded. I compared the pics of mine to one online and that piece was missing. There is noise coming from the rear differential. I am not sure f it can be saved and how sturdy it would be if I tried to drill out the bolt

[20BELLO]

The mounting for the rear differential is to the rear subframe, it should be pretty strong. Never heard of anyone with an issue like this before, so Id suspect a defect in the construction of the bolt. You can get new bushings from various places, Energy Suspension sells some. You may be able to buy the bolt from a local hardware store.

If you get a new differential, the M35 and M45 are different. However, you CAN mount an M35 or a G37 differential with just a little bit of work onto an M45. Though if you use one of these other differentials then you also need new axles too as the size, bolt pattern, and spline count dont match up. If you go with a G37s rear differential you can get about 10% faster acceleration just from the differential swap due to the gearing change.

I found a used m45 rear diff so I probably would not use a G37 because I just want the car to move at this point. i only had this car foe less than 5 months and already having to put money in to it.

[svard75]

Sorry to hear this.

I always plan to spend about 20% of the cost of the car on the first year of ownership on maintenance or break\fix. This is regardless of brand.

[20BELLO]

Sorry to hear this.

I always plan to spend about 20% of the cost of the car on the first year of ownership on maintenance or break\fix. This is regardless of brand.

Im a mopar man and my family convinced me to buy Infiniti. I had a infiniti qx4 and it never gave me any major problems. the M is such a beautiful car im so angry that its just sitting pretty in the garage…..

[06M4.5]

Can't say that I've seen that before on an M