We loosened one of the ZF to bell housing bolts when we were doing the lift to put the engine in. I can't find the torque spec for those bolts to tighten it again. I know the bell to block is 25 FtLbs. What say you?
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I did not know this but it varies by the grade of bolt you are using. Higher grade bolts require more torque to achieve the same clamping force (so says the web). I would think the bell to block is more than 25. They are 7/16 - 14" bolts? Same with ZF I believe? Will be curious to hear what others say here.
I use these guys and their resource pages are excellent:
Here's one web input:
My 70 book says 40-50 ft-lbs bell to eng.
28-40 bell to trans case
That's for a Mustang
@panterapatt posted:I did not know this but it varies by the grade of bolt you are using. Higher grade bolts require more torque to achieve the same clamping force (so says the web). I would think the bell to block is more than 25. They are 7/16 - 14" bolts? Same with ZF I believe? Will be curious to hear what others say here.
I use these guys and their resource pages are excellent:
I disagree, higher grade bolts support a higher tightening torque if you want to apply a higher clamping force, but for a given tightening torque the axial force is the same regardless of the grade of steel.
What modifies the axial force for the same torque is the surface condition of the threads and the lubrication.
For standard 10 x 150 metric bolts, the typical applied torque is 50 Nm, or 37 ft-lbs. If you use high-grade bolts, it can go up to 70 Nm, or 52 ft-lbs, and with the best ARP lubricated bolts, up to 70 ft-lbs, or 95 Nm.
https://arpcatalog.com/37/#zoom=true