Transfer/Transmission cross member attach bolts/spacers

[bl71236]

Hello All,
Been stripping the M1009 frame down for powder coating and was wondering what the purpose of the spacers on the cross member attach bolts are.
I at first thought it was a mistake . However after consulting the TM parts manual it shows them . And also I was wondering why the r/h set is on top and l/h is on the bottom. If someone could shed some light I would appreciate it. Thanks in advance and Merry Christmas.

 

[87cr250r]

It gives the bolt a longer grip length. It makes it so the bolts are less likely to loosen or break. The grip length is the distance between the head of the bolt and the first engaged thread. The longer the grip length the less strain the bolt sees for any displacement that occurs.

Think about tightening head bolts vs lug nuts. Even though the torque is the same, the longer head bolt takes a lot more effort to tighten or loosen due to the difference in grip length.

If you ever have a problem bolt that loosens or breaks, use a longer bolt with spacers. This is especially true for exhaust manifolds.

 

[andyh1956]

GM put them there so when you install that 4" lift you can remove them from the top & use them to lower the crossmember an inch for better rear driveshaft angle. GM was smart like that back in the day...

 

[bl71236]

It gives the bolt a longer grip length. It makes it so the bolts are less likely to loosen or break. The grip length is the distance between the head of the bolt and the first engaged thread. The longer the grip length the less strain the bolt sees for any displacement that occurs.

Think about tightening head bolts vs lug nuts. Even though the torque is the same, the longer head bolt takes a lot more effort to tighten or loosen due to the difference in grip length.

If you ever have a problem bolt that loosens or breaks, use a longer bolt with spacers. This is especially true for exhaust manifolds.

Hadn’t thought of that. Makes sense. Thanks for the fast reply and insight.

 

[bl71236]

GM put them there so when you install that 4" lift you can remove them from the top & use them to lower the crossmember an inch for better rear driveshaft angle. GM was smart like that back in the day...

Ha ha

 

[nyoffroad]

GM put them there so when you install that 4" lift you can remove them from the top & use them to lower the crossmember an inch for better rear driveshaft angle. GM was smart like that back in the day...

I like this answer better!