Hello everyone,
I'm new here and came to where the Mack folks hang out because I have an issue with my 8LL.
I have been running Macks for 43 years in the dirt. This problem is in a quad axle, 97 Mack cl700
I'm an owner operator and know evey clunk and odd sound and pay attention to it, and fix it myself usually.
The other day I took a load into a soft dump site, this is the first time out in the spring for this truck.
The backin was showing some stress so I stopped put it in low low, and drove right out, maybe half throttle max. Back in for a flat dump and the pulled out no problems about 70000 was the haul. I've been in much worst with this truck.
Read to roll back for another load and pu it in direct, but nothing, neutral.
Back in LL and it drives fine all gears and reverse, no strange sounds but main stage and high are neutral.
Drove it 3 blocks back to my shop at about 10mph and began to work on anything obvious.
No air leaks, checked reg /filter, pulled the splitter valve and clean it and checked orings.
I can hear all the clunking when shifting the stages, and if I sit at 1000 rpm in direct low, (not low low) with it in 1st gear it is just neutral but every once in a while it will grumble and slightly move like it's trying to connect.
But still LL seems to work fine. Obvious I won't work this way.
1000 a day down time. They've been so good i had never had to do much to them, I'm a good mechanic but don't have any time with these 8LL
All tech advice welcome.
And thank you.
Also, I away follow up with final result to help others with the same problems
