1978 Pete 359 with Rockwell SQHD tandems. Original axles to truck (verified by serial numbers on peterbilt build list for the truck). Locker switch on the dash (air switch). Found out that it is disconnected inside the dash and the line is capped. Is there a good reason that this was disabled? Were the PO farm hands using it too much like a 4x4 in the fields? What am I risking in hooking it back up assuming there is not a leak in the air lines going back to the axles? Could have used it this week in a altercation with muddy conditions. John
Hook it up chalk the wheels and release the parking brake. Jack up any one of the axle end tire assemblies and trans in neutral. With the power divider unlocked tires should turn by hand. P/D locked they should not and make sure they unlock. Good to go. Some differentials also have axle locks which lock the the axles on both sides on the same differential together. All of the ones I have seen had a P/D switch and a seperate axle lock switch but have read of veryations to that. Never saw anything but the P/D lock on the SQH series.
I bought a parts truck a while back that had the power divider switch blocked off-didn't think anything of it at first, but when I pulled the drop-ins (SSHD) to use on another truck I found that the front and rear were different ratios-it kind of made sense then!
Wymon, Good point. I confirmed that the first axle serial number was correct. Did not crawl under to check the second, just assumed it to be there. Will check. Thanks for the info! John
