Why is diff 1/2 inch too long

[biker]

I have just installed a new R180 diff into my 240Z. The problem being is that it seems too long to fit.

If I bolt the front cross member on, I can't get the propeller shaft on. I disconnect the front cross member, I can get the prop shaft on but the holes won't meet on the cross member and the chassis.

It looks the same as the old one with the exception of the front flange pinion, old one is square, new one is round. Still same length though (42mm).

It bloody 42 degrees here in Oz (that's 110 F in the shade) and I have been under this bloody car all day in the western sun. I am totally PXXXXd off!!! Even had the missus under the car with me (helping, nothing else - too hot))

Any suggestions???????

biker:disappoin :disappoin

[panchovisa]

Is the new diffy the same length from input flange to back aluminum cover? Are you putting front cross member back on with cut out for exhaust on the correct side? My guess is that the answer is yes to both, but just thought I'd ask.

I would loosen the two nuts that hold moustash bar (rear diffy bracket) to the car. This will allow m-bar to move backwards slightly. I would also back out big bolts in front of a-arms. This will allow a-arm bushings to "relax" and lengthen out.

I would attach the front cross member loosely, reposition the metal/rubber front diffy mount as far back as possible, install the diffy, tighten m-bar nuts, tighten crossmember bolts to car, attach prop shaft, and finally tighten big bolts thru bushings.

If you want, grind hole thru front cross member elongated toward the front. I think the main problem is the m-bar is pre-loaded by old bushings to move forward and it is just to hard to get any leverage when your on your back with a diffy on your chest to push it backwards.

Crack open a Fosters and give it a thought! Or two! (Fosters, that is)

[biker]

Thanks for your help Panchovisa

Turns out that it was a combination of a new diff using an older front mounting. It has been explained that they changed the diff angle after a couple of years by offsetting the single mounting bolt by around 30mm.

Extremely frustrating but got the diff back in and am quite happy with it.:classic:

Biker

[panchovisa]

biker, glad all is well. Thought maybe you blew up the car (after too many Fosters) from heat/alcohol induced delerium.

[biker]

All went well for the weekend and I even set a peronal best for the track. Howver, I blew my gearbox up on the way home. It s ok as I have only lost 5th and reverse - don;t need them that often anyway.

Strange thing is that after the drama of taking 6 days to get a diff in, nothing looks hard anymore, even a blown gearbox. I'm smiling!!!:classic: :classic: