Trans questions

[wingman]

Got a few questions for the trans specialists. I have a B65 with a 10sp unishift and the spliter valve is broken and also missing the shift knob cover. Is the operation of the factory air spliter the same as the range valve on a roadranger. I have a few of those and would be an easy conversion to mount on the stick. Next question- if I can't fix it I have a TRD-72 from another truck. I have heard that it is a 9speed and then the wiki says it is a ten speed. It also has the linkage for the auxilliary box on the outside of the box. My TRD-67 duplex is all internal. Any help is appreciated.

[GreenGiant2]

i see you have some brockways, lets see some pics, 361 and 758 and others if you have them.

gg2

[Superdog]

I don't see why that wouldn't work. An old friend of mine had a H63 back in the day with a Unishift,he said he had plumbed his splitter to the front brake limiting valve when the splitter on the knob broke.

[doubleclutchinweasel]

Got a few questions for the trans specialists. I have a B65 with a 10sp unishift and the spliter valve is broken and also missing the shift knob cover. Is the operation of the factory air spliter the same as the range valve on a roadranger. I have a few of those and would be an easy conversion to mount on the stick. Next question- if I can't fix it I have a TRD-72 from another truck. I have heard that it is a 9speed and then the wiki says it is a ten speed. It also has the linkage for the auxilliary box on the outside of the box. My TRD-67 duplex is all internal. Any help is appreciated.

Any air valve should trigger the splitter, like Superdog said. It just has to be plumbed in properly, or else it might work backward!

A TRD-72 SHOULD be a 10-speed Duplex, direct drive. That is, 5th gear should be direct (1:1).

For a 9-speed, which is an overdrive model, it SHOULD be a TRD-720. The "0" generally means high gear is overdrive.

But, I have heard folks argue over whether they had a 9 or 10. Every 9-speed I ever saw was an overdrive. But, hey! We ARE talking about Mack here! Anything is possible!

The "72" is the basic 5-speed box. It could be coupled with a 2-speed rear section for a Duplex (TRD), a 3-speed rear section for a Triplex (TRT), or a 4-speed rear section for a Quadruplex (TRQ).

There are also variations on the basic numbers, indicating different gear ratios and torque capabilities (like a TRQ-720, TRQ-7210, or TRQ-7220, indicating 3 different versions of a Quadruplex).

Direct drive setups typically have as many gears as it appears (5 X 3 = 15 or 5 X 4 = 20). But, when you add the overdrive 5th gear, some of the combinations are duplicated, so they discount those (5 X 3 = 13 or 5 X 4 = 18, where a couple of the gear ratios are essentially the same). On an 18-speed, for instance, LO-SPLIT 5th is essentially the same as DIRECT 4th, and DIRECT 5th is essentially the same as HI-SPLIT 4th, So, those two don't really count. They're there...I've used 'em. You just need to not down-shift or "nothing-shift" by accident!

Nice thing about the TRQ-720 overdrive Quadruplex (or equivalent TRT-720 Triplex) is that you get 2 overdrives (HI-SPLIT 4th and HI-SPLIT 5th)!

Enough jibberish? Sorry! Here are some shift plates. The 10-speed and 15-speed shown are DIRECT models. The 18 is an OVERDRIVE model.