What is the difference between 4707 and 4515 brake shoes?
Takeaways from the Haldex guide are: 4515 style brake shoes have a hump on the web (the web is the center rails that hold the roller pins and hardware), but 4707 style brake shoes DO NOT have a hump on the web (BE ADVISED THIS IS NOT ALWAYS THE CASE, USE THE OTHER FOLLOWING METHODS TO VERIFY) 4515 style brake shoes have 4 holes on one side the brake shoe table (the table is just a fancy word for the brake shoe metal base that holes the brake shoe lining with rivets), while 4707 style brake shoes have 3 holes on one side of the brake shoe table 4515 style brake shoes have the rivet holes in the 4 hole groups starting at 3/8 in. from the web (again the web is just a fancy word for the center rails that contain the roller pins and hardware), while 4707 style brake shoes 3 rivet hole groups are spaced 5/8 in. away from the web Takeaways from the Meritor guide are: 4707 style brake shoes MAY OR MAY NOT have a hump, do not be deceived Some 4515 brake shoes may have a cast iron brake shoe table aka base (this will be an obvious difference) 4515 has a few variations of length between the larger roller pin slot and the nears spring pin hole (view pictures on pg. 12) 4515 looks visually different, for example; some 4515 have contained holes for the roller pins instead of slots on the ends for the roller pins like the rest of the brake shoes (view pictures on pg. 11-12)
How to fix an air leak on a semi truck? / How do I find an air leak in my truck?
Check for air leaks with these 3 procedures: Remember these procedures need to be done when the truck has more than 100 PSI, but best if they are done right after the truck purges, notifying you its at maximum pressure, also soap and water in a spray bottle make identifying a lot easier Parking brake (yellow tractor air supply knob) set / pulled out, walk around the truck or trailer and listen for a *hissing* noise Parking brake (yellow tractor air supply knob) set / pushed in (MAKE SURE YOU CHOCK THE WHEELS TO PREVENT THE TRUCK FROM ROLLING), walk around the truck or trailer and listen for a *hissing* noise Parking brake (yellow tractor air supply knob) set / pushed in AND the brake pedal firmly pressed (this will require 2 people), walk around the truck or trailer and listen for a *hissing* noise.
