I have a repair manual, but it does not include a diagram for the air lines, trying to diagnose a shift problem, one guy took the airlines off, another guy put the airlines on, and now I have to figure out why no high side. Need a diagram for the airlines.
Only 3 lines swap a couple... if that don't fix it put em' back and swap 2 more... sorry I don't have a diagram but I'll bet someone here has one handy.
Depending on slave valve on side of gear box. Air pressure feed from regulator to front bottom of slave, Low range on top of slave, High range from middle of slave. If it comes out backwards swap the air lines at the top range cylinder. Shifter lines-Black is pilot to back side of slave, red goes to the front port on slave, Green goes to tee in low range hose on top of slave, and blue to splitter. Two types of valves used A4688 and A5000 hose routing differs slightly from one to the other. More than likely your dealing with a A5000.
mouse over https://www.pepinstruckparts.com/st...VALVE_FOR_18_SPEED_RTLO-18918B,_EAT10101.html
Hard to find but I found these on Eaton website this morning, I believe they had the high and low side lines backwards on the range cylinder, swapped them this morning, couldnt test drive garage door came off track yesterday.
Well after replacing the range valve on the side of the transmission now have air switching between the hoses on the range cylinder, however have low range and neutral, once in a while if you move the range selector multiple times you may get high range.
The valve on the side is the slave valve, the one on the rear-top right is the range cylinder. More than likely the bore and O-rings in the range cylinder are dry. Squirt some air tool oil into both hoses going into the range cylinder, reconnect hoses, build air and operate the front range selector on the shifter. Usually after a few shifts it starts working and a little faster each time.
Can the range cylinder be disassembled in the chassis? obviously not the shift fork. I used air tool oil, ran it numerous times, and drove it around the yard, however if driving it down the road it will slip out of high range, must have a problem in the shift cylinder, or I guess I will have to remove the back box. Drove truck home from the auction in december, just fine then it has been in the shop for restoration all winter.
Unbolt the range cylinder cover and check to see if the nut on the end of shift fork shaft is tight, plus see if it is dry in the bore. Yes the rear section can be removed using two 1/4 thick steel straps and three bolts to hold the counter shafts in place.
Years ago I built a bracket to lift the back box off with a floor jack, and the holding fixture to time the counter shafts. Turns out the diagram above has the air lines for the range cylinder backwards.
Not surprised Stuff on line and manuals have so many mis-prints a person has to recheck everything they do. And there are several things wrong in that diagram.
Took the range cylinder apart tonight, nothing wrong in there, will be pulling the back of the box apart, must be an issue with the range fork or the sliding clutch. I have done this proceedure in the past, have the holding fixture, countershaft retainers, and holding block but will be looking at the eaton fuller site for in frame repair on removing and timing the back box in chassis.
Low/high range synchronizer, High possibility it lost the lining in the hub, the old Garlock lining would last. Eaton changed the type of lining about 25 years ago. Possibly a broken slider pin in the synchronizer assembly. The forks can wear but extremely rare for one to bend.
I pulled the back of the transmission, replaced the synchronizer, the fork (worn out), the high range gear ( wore out), and the rear bearing which the shoulder was broken. But what a Bitch to get back in the truck, I have done this proceedure years ago, and forgot what a pain it can be. I could have removed the transmission in the time I have into getting this back box back in the truck. I made some brackets years ago to hold the countershafts, but I still dont think the counter shafts are being held up enough to get into the bearing races.
It's much easier to just remove the whole gear box stand it on end and remove and replace the rear section. Plus it's the best way for setting preload on the counter shafts. Much more accurate.