Rear differential - broken ring gear teeth - Page 2

SierraHawk · 02-05-2012, 08:35 AM

carringb - I understand a little about the mechanics of ring and pinion sets but this is where I get lost.

The old ring and pinion set was a Dana and the pinion was marked "-1" They set the shims at 0.075 on the old pinion. I cannot find the 0.075 setting anywhere on the Dana chart but it sounds like a shim stack of 0.075 would have shoved the pinion too deep into the ring gear.

The new ring and pinion are Dana and the pinion is marked with a "0". It was installed with shims that are 0.045 thick.

The two teeth were not broken off near the edge of the tooth were I would have expected if the damage was caused by abuse. I am 62, retired and, like most of you, do not drive my van in an aggressive or abusive manner.

It looks like the base of the pinion teeth were stressed so severely that they literally pulled steel out of the pinion body. Did the wrong set up on the pinion cause so much force on the body of the tooth that over time the steel fatigued and caused the tooth to literally pull steel out of the pinion body at the base of the gear? Or is there another explanation like the gear itself was flawed?

Ford-6.0 - Thanks, I did send Dana an email through their system.

carringb · 02-05-2012, 10:01 PM

Quote:

Originally Posted by SierraHawk

The two teeth were not broken off near the edge of the tooth were I would have expected if the damage was caused by abuse. I am 62, retired and, like most of you, do not drive my van in an aggressive or abusive manner.

It looks like the base of the pinion teeth were stressed so severely that they literally pulled steel out of the pinion body. Did the wrong set up on the pinion cause so much force on the body of the tooth that over time the steel fatigued and caused the tooth to literally pull steel out of the pinion body at the base of the gear? Or is there another explanation like the gear itself was flawed?

The wear at the inboard edge of the ring gear teeth tells me setup was off, or something moved. The bearing marks on the pinion shaft lead me to think the setup changed, probably because the pinion nut wasn't tight enough.

The pinion teeth were point-loaded by the edge of the ring gear teeth.

When my pinion gear broke (on my 4.30 set) it was from a hard impact, after I had already weakened them by severely overheating them.

SierraHawk · 02-06-2012, 09:33 AM

Last week I called the shop that did the original rebuild. I was told that they will not warranty the parts or labor. What he is working with is the 10 months that have elapsed to justify his refusal to honor their work or materials. But he has forgotten about the fact that I took the van into his shop at 1000 miles after the rebuild and complained about the unusual heat that was being generated by the gears. The diff was so hot that water splashed onto it evaporated instantly. The shop owner told me at the time that the heat was due to the hot daytime temps (April ?) and that the diff was close to the muffler. In this case there was no hard impact. The first gear broke while I was driving up a slight incline at 40mph.

webbmac · 02-06-2012, 12:06 PM

I would report him to the appropriate NV state licensing board. Here in CA, it's called the Bureau of Automotive Repair (BAR). The excuse of the diff heating up because of proximity to the exhaust is comical, it would need to be a blow torch pointed at the diff.

SierraHawk · 02-06-2012, 12:35 PM

I cleaned some of the oil off of the ring and pinion teeth. I don't know what they look like when they are new. The machine groovs on the edge of the pinion teeth are polished on the toe and heel. Between the heel and toe area the machine grooves are distinct and not polished. The edge of the pinion teeth appear to have a slightly black patina covering them in the middle between the toe and heel polish.

vandiesel · 01-02-2021, 03:17 PM

Old thread but what was name of the shop that did this so I can tell my buddy to avoid it? Anyone have a good shop for running gear diagnostics and repair in Vegas?

arctictraveller · 01-02-2021, 05:10 PM

I don't know if this is the shop the PO used, but I had a good experience at Axleline on Watson way in Sparks. They got me in on an emergency basis and did some front axle repairs, but not the differential. It looked like they worked on a lot of drive lines and axles.

vandiesel · 01-02-2021, 05:50 PM

Quote:

Originally Posted by arctictraveller

I don't know if this is the shop the PO used, but I had a good experience at Axleline on Watson way in Sparks. They got me in on an emergency basis and did some front axle repairs, but not the differential. It looked like they worked on a lot of drive lines and axles.

Thanks! Exactly what I was looking for.