Tinman22

.71 w/5.02 rears and standup 24.5s is 72 mph at 2100 indicated.

Mack shift valves and Eaton shift valves are not interchangeable. There are no threaded Mack 13 speed shift valves available. You will need a new style shift lever. The double check valve should be fed by the primary and secondary air tanks. Blocking off one side will eventually result in air supply failure as the check valve shuttle seals wear. Driveshaft will need to be cut 5.25 inches. 2130’s from ch series trucks will need the R model clutch arm due to differing offset. The new easy pedal clutch’s do not need the grease pipe adapter. The bottom zerk is accessible. Transmission jack adapters for the Mack transmissions (200 and 300 series) are almost impossible to find currently. I found a new set and bought them then duplicated them for myself. Mack recommended synthetic (85-140) is noisy in this particular trans. Regular oil (also 85-140) quieted it down. 3/16 air line for the Mack shift valve is getting hard to find in my area. I found some covered in dust at a local shop. Make sure you have some on hand.

I understand how it all works. The problem has been finding a 13 or 18 speed knob either older round with a three position switch or newer with two switches that is threaded and not an Eaton/fuller knob. The knobs being sold online and at mack are hollow and slide over a tapered shifter and are held on with a top nut. Mack knobs are also marked differently for the air lines than the Eaton knobs. No big deal if they do the same thing. Problem is I’m being told by people that I would assume know more about the intricacies of shift knobs say that Eaton knobs apply air in the opposite way a Mack knob does. To compound my confusion almost all knobs for sale online or parts vendors are using a generic photo of a knob half the time and say that they fit everything from Eatons to waring blenders. So today since my flywheel and driveshaft aren’t back I’m going to the truck salvage yard and buying every different 13/18 speed knob I can and comparing their operation and markings.

Hmm….is it thread size? Internal ? The new one I got isn’t even threaded,looks like it mounts on a tapered shaft with a top nut. Guess I’ll just start buying knobs and hope I figure it out.

I’m having a hard time getting a good part number for the early chrome round Mack 13 speed shift knob. It seems half the vendors say it’s the same as an Eaton fuller the others say it’s not while 1/3 say it’s good for both. Any help?

So I could just t into a supply line and feed it air since the double check function of the valve isn’t really checking anything.

That is what I will do then. I wonder why they want a double check valve with only one supply line? Doesn’t leave much to check. The diagram on the Bendix site shows it as a check valve between two feeds like a trolley brake and a foot brake allowing whichever has the higher pressure to operate the del side.

Ok. So on the dc-4 check valve it shows two supply and two del.. Looking at the schematic there is only the one line coming from the double check valve. So plug the other supply and del ports.

No it does not. I thought I had it right it said without compound neutralizing for pto.

Thanks for the answer. I looked at that one but wasn’t sure. It shows two supply lines. Where should I pull them from. I don’t see one for the nine speed.

Also does anybody have a good part number for the correct double check valve?

Does this look right

Does anybody have a simplified diagram for shifter/transmission air line routing? I have the factory service manual it looks like fig.544 page 205 is close. I don’t have a double check valve as indicated do I need one?

I didn’t think so but I’ve been known to get things wrong. Thanks.

So the 2090 finally decided to retire so I sent the 2130 out for a rebuild. Besides the obvious (clutch set,trans brake,rear main,cooler and lines,shift knob) is there anything I’m missing in the way of air controls? No p.t.o.