Is anyone aware if there was ever a published spec to measure it?
If I'm not mistaken most chains you measure between the pins, but I would think that deflection would be another way to measure, at least to get a rough idea of condition. I checked the 1991 R/V Service Manual, unfortunately by that time rebuilding transfer cases by the mechanics was apparently not done.
I know most say just run the chain as is, but the one case was bound up when I got it (looks like whoever was in there last over-RTV'd everything and the chewed up bits from that locked it up for hand turning, if not starving it of oil) and the chain slop is massive IMO, the other case I don't have apart yet, but I don't know what it ran like.
To top it all off, I've found threads where people have had problems with aftermarket (chinese) chains, so just buying a replacement is not a 100% solution. GM chain is ~$200, aftermarkets are around $80. Not sure how you'd know anymore what was coming from china.
I love being able to reuse stuff, but I'd hate to throw a case together and in the truck, only to have to pull it apart again.
Edit: On the second case I just took apart, measuring deflection where I got the most chain movement, it was 3/4". That includes the movement of the output shaft as it's not supported in the rear at that point. Chain is marked "Morse". Appears to be in good shape, but unless/until I put the other case back together, won't be able to measure deflection on that one to compare.
If I'm not mistaken most chains you measure between the pins, but I would think that deflection would be another way to measure, at least to get a rough idea of condition. I checked the 1991 R/V Service Manual, unfortunately by that time rebuilding transfer cases by the mechanics was apparently not done.
I know most say just run the chain as is, but the one case was bound up when I got it (looks like whoever was in there last over-RTV'd everything and the chewed up bits from that locked it up for hand turning, if not starving it of oil) and the chain slop is massive IMO, the other case I don't have apart yet, but I don't know what it ran like.
To top it all off, I've found threads where people have had problems with aftermarket (chinese) chains, so just buying a replacement is not a 100% solution. GM chain is ~$200, aftermarkets are around $80. Not sure how you'd know anymore what was coming from china.
I love being able to reuse stuff, but I'd hate to throw a case together and in the truck, only to have to pull it apart again.
Edit: On the second case I just took apart, measuring deflection where I got the most chain movement, it was 3/4". That includes the movement of the output shaft as it's not supported in the rear at that point. Chain is marked "Morse". Appears to be in good shape, but unless/until I put the other case back together, won't be able to measure deflection on that one to compare.
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