[DoctorDex]

I measured the total backlash at the rear dif. today and I found it to be 7 mm, whereas spec. is 5mm. I measured the 7mm of backlash with the car in neutral, as per manual instructions. Just for kicks, I tried measuring the backlash with the car in gear and I was unable to move the shaft at all.

I was talking with my neighbor, a heavy duty mechanic, about this backlash issue and I took him for a ride to show him how bad it actually is. He pointed out to me that it is actually two clunks in rapid sucession. The first clunk is quieter and it is only a fraction of a second before the second larger clunk. He thought that maybe it could be due to the propeller shaft yoke or lobro joint slamming into its mating part. He reasoned that when you apply a large amount of torque to the rear dif., the rear dif. wants flex upwards and forwards. This upwards and forwards motion is what slams the shaft components into one another. He also said that the dealer probably only adjusted the crown and pinion. However, if the dealer had adjusted my crown and pinion, wouldn't I hear an awful whinning noise from the rear dif.? My neighbor is of the opinion that the majority of the backlash would be between the side gears and the spiders.

Does any of this stuff make sense or are any of these ideas plausible?

Thanks.

Declan