Gearbox and Diff Woes

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DCMVan70
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Gearbox and Diff Woes

Post by DCMVan70 »

Hi All

I recently suffered a gearbox failure. Dropping into 3rd, there was a vibration and then some loud bangs and noise from the clutch housing. The reconditioned gearbox was just over a year old, but fortunately the supplier agreed to cover under the warrantee, which was great. The photo below shows the damage.
Gearbox failure
Gearbox failure
IMG_7820.jpeg (2.66 MiB) Viewed 707 times
I swapped the GB over and was reversing out of my drive when I heard a clunk from the rear of the car - then another and then no drive. I jacked the van up and it was obvious that something was wrong with the diff or axle, so I pulled that. The half shafts are fine, but I am missing teeth on both planetary gears - one side only shown below.
Debris from diff
Debris from diff
IMG_7832.jpeg (2.34 MiB) Viewed 707 times
Diff failure
Diff failure
IMG_7833.jpeg (2.57 MiB) Viewed 707 times
My question is if this is a common thing to have both the GB and diff fail at the same time - could the shock of the GB failure have caused the diff to lock and fail? I am in a van with a 1275 A+ engine, but no extra performance mods and the diff is a 9/38 or 4.22, which I don’t think would have been standard, but probably suits the engine well?
Is there anything else I should be looking for to cause this to happen?

Regards
David
philthehill
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Re: Gearbox and Diff Woes

Post by philthehill »

It is not unusual for the sun and planet gears to fail. I suspect that the sun and planet gears were already on their way out and the shock from the gearbox failure gave the death sentence to the diff.

DCMVan70
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Posts: 64
Joined: Tue Jun 23, 2020 10:14 pm
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Re: Gearbox and Diff Woes

Post by DCMVan70 »

Thanks Phil
I am ordering up a recon diff
Cheers
David
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