TownsendMack Posted December 12, 2023 Share Posted December 12, 2023 Hauled 14 tons this afternoon on the highway and started noticing a whine coming from, what I assume, to be the transmission. The truck had trouble going into Hi, and noise was more pronounced in 3rd gear. What are some things to rule out and figure out how much this will cost? Synchro, shift cylinder, solenoids, shift fork, hot oil, differential noise disguised as tranny noise? I feel like it is odd to have issue more prominent in 3rd. Could this be diff noise traveling up drive train? Does this sound like a tranny swap is in order? What does a tranny repair look like for these units? Can these be swapped with an Eaton? Thanks for your knowledge, time, input. Quote Link to comment Share on other sites More sharing options...
BOBWhite Posted December 12, 2023 Share Posted December 12, 2023 Troubles seem to start in the rear HI-LO boxes on these Mack transmissions. From what I've heard rebuilds are tricky and not to many around to do it anymore ($). They can be swapped out for an Eaton but Im not sure about airline and clutch specifics. If your wanting to keep the driveline all Mack I'd look for a 12 speed, they're really nice if you do a lot of backing and seem to hold up pretty well. Quote Link to comment Share on other sites More sharing options...
TownsendMack Posted December 12, 2023 Author Share Posted December 12, 2023 Thanks. So what in the hi-lo box starts to go? Is it somthing that can be caught and dealt with early after indication? Whats the tricky part to these rebuilds, finding parts? Appreciate the advice. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted December 12, 2023 Share Posted December 12, 2023 What's tricky is supporting the rear counter shafts. There is a special tool to insert through the top rear cover, and 4 'Z' brackets to use after you remove the rear cover. You can make the 'Z' brackets... do you have a sbc manual? Quote Link to comment Share on other sites More sharing options...
TownsendMack Posted December 13, 2023 Author Share Posted December 13, 2023 I found a 500 page progear manual online. Any reputable places to source parts? Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted December 13, 2023 Share Posted December 13, 2023 In my area, I used "overdrive rebuilders".. they have PAI parts. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.