Bent Rear Diff Bolt

[ARC]

Meh, been dealing with two bolt issues since I was jump started...


View attachment 17973

This was a good one!

 

[Cdubya]

Is removing the bolt essentially just supporting the diff with a Jack and then removing the old bolt and swapping in a new one? Or is there more to it? Pry a dumb question but if I wanted to see if my bolt was bent I didn’t know if it was something easy to check

you got it

 

[TXCarbonized]

Well at least the bolts are bending instead of breaking now. I wonder if they adjusted the material or heat treatment of the bolts to make them less brittle.

 

[Cdubya]

So I have the two bolt subframe. MY2020 Build 6/2019, 66k miles. Replaced the two bolts with the new part# bolts today in about 20 minutes.

Findings? Existing bolts were not bent at all and appear to be equivalent to the new part# bolts (grade 10.9).

My conclusion? If you have a two bolt, it may not be worth it to replace the bolts with the new part#. Did the part# change because it's a stronger bolt or for some other reason besides that? We may never know for sure.

 

[Dale5403]

Here is an explanation of metric bolt marking. According to this, nothing changed.
https://wilsongarner.com/understanding-metric-bolt-and-screw-grades-head-markings/

 

[FORZDA3]

Here is an explanation of metric bolt marking. According to this, nothing changed.
https://wilsongarner.com/understanding-metric-bolt-and-screw-grades-head-markings/

Different manufacturer, same specs.

 

[Cdubya]

Here is an explanation of metric bolt marking. According to this, nothing changed.
https://wilsongarner.com/understanding-metric-bolt-and-screw-grades-head-markings/

They are both 10.9 bolts, yes, but what if the original bolts were not manufactured properly--like they weren't fully heat-treated? It just seems weird that some of the bolt failures posted look like they were just sheered off.

To me though, the fact that my two bolt setup had bolts that showed no signs of being bent, shows the problem is more that they used a single rear mount setup instead of the two rear mounts that the engineers had intended, rather than a problem with the bolt.