New Shift Knob for RoadRanger

[doubleclutchinweasel]

Range selector valve is leaking. Old "bat handle" knob is worn through, and too tall. Looks like something off one of Ed Roth's cartoon cars from the '60s! The 5/8-11 to 1/2-13 adapter they used adds another inch or so to it.

Picked up a new-style Eaton-Fuller knob, with built-in range valve.

Now, I'm making a drill jig to mount on top of the stick (after I cut it off) to allow precise drilling & tapping of the stick. I'm gonna cut the stick off, and drill & tap it to the 1/2-13 thread size on the new knob. Then, I'll put a long grade 8 set screw in the hole, and thread the knob on. Rather than screw the knob on and use jam nuts to lock it in place, I will use a washer of correct thickness to "index" the knob on the stick. That will be a little more work, but it will be VERY clean.

I looked at the actual 15-speed knob. But, according to Fuller, you have to change the cover on the deep reduction slave valve on the transmission to make it work. Must be a little different logic to the air circuit. No matter. The hi-lo range is the important one to me. And, it is supposed to require no modifications.

As soon as I get the various bits and pieces made, I'll try to document the whole process in pictures. I know, I suck at that! Always run short of time and forget to take the pictures! I'll try to do better on this one, Vinny!

More pics to follow (we hope!)...

[doubleclutchinweasel]

Drill jig in place with 3/16 bushing

[doubleclutchinweasel]

3/16" pilot hole.

[doubleclutchinweasel]

Drill jig with 27/64" bushing.

[doubleclutchinweasel]

Drill jig with 1/2-13 tap bushing.

[doubleclutchinweasel]

Using jig to file top of stick square and "index" knob.

[doubleclutchinweasel]

Set screw in place.

[doubleclutchinweasel]

Finished knob installed.

[doubleclutchinweasel]

_{This looks and feels SOOOO much better now!}

In reverse, it's about the same height as the bottom-right section of the steering wheel.

[other dog]

lookin' good, a job done right!

[farmer52]

Nice job!

[doubleclutchinweasel]

lookin' good, a job done right!

Nice job!

Well done!

A square peg and round hole is not a problem for Mack people.

Jim

Thanks, everybody!

This was a lot more work than welding a bolt on top of the stick. But, it should be very durable...and it's certainly cleaner!

[Green Dash]

Nice work.

You can't beat the old one for cool looks, but your hand will certainly appreciate the new one!

[doubleclutchinweasel]

Nice work.

You can't beat the old one for cool looks, but your hand will certainly appreciate the new one!

Exactly!

[umodelnut]

Hey look at that looks nice!!!

[Speed]

If I may tag a question on here-That "-valve you showed. I have one that looks like that but is marked for a 2 speed axle;could it be used on the vacuum Spicer 1350 2 speed axle on my '54 GMC? I'm not sure it'd flow enough volume to shift it quickly enough.

Speed

[rsb502]

Just out of curiosity, why isnt it a Mack shift knob? that is an excellent installation job I might get you to come help me with some projects. ( I like the old Chrome round Eaton knobs they look hard core old school).

[doubleclutchinweasel]

If I may tag a question on here-That "-valve you showed. I have one that looks like that but is marked for a 2 speed axle;could it be used on the vacuum Spicer 1350 2 speed axle on my '54 GMC? I'm not sure it'd flow enough volume to shift it quickly enough.

Speed

Hey, Speed.

The way this valve is ported is like this. When the range select lever is "down" (LO), the "supply" port is connected to the "delivery" port, which feeds the slave valve/cylinder. When the range select valve is "up" (HI), the "supply" port is closed-off, and the "delivery" port is exhausted to the atmosphere.

As long as your 2-speed valve is similarly ported, then I don't see why it wouldn't work. I mean, pressurized air and vacuum are similar systems. They both work on a pressure differential. The primary difference is the AMOUNT of pressure differential you have to work with. With pressurized air, you can get more work out of it. But, if the system is already functioning correctly on vacuum, then the cylinder sizes and mechanical devices are, by definition, already properly sized to do the work required. Remember, the control valve is just that; a CONTROL vavle. It doesn't do the actual work; the cylinders do.

So, as long as the porting works like I described above, it SHOULD work. If you are concerned about flow rates, and the associated time/speed of the system, you might consider using slightly larger lines. Mine are the original 1/8" lines. I believe most newer stuff uses larger 5/32" air lines. This will provide slightly more available "buffer" air, which should improve the function slightly.

The actual threads in the new valve are 1/16" NPT. So, this may somewhat limit both the maximum airflow through the fittings, and the variety of fittings available.

The original T-valve used 1/8" NPT fittings, just for the record.

The new valve works exactly as well as the original did on my truck. I can't tell any difference at all with the smaller fittings. But, again, the actual work is being done by the slave valve/cylinder. This valve just tells it what to do!

Hope this helps. Let me know if I can clarify (confuse?) the issue any further for you!

Kent

[doubleclutchinweasel]

Just out of curiosity, why isnt it a Mack shift knob? that is an excellent installation job I might get you to come help me with some projects. ( I like the old Chrome round Eaton knobs they look hard core old school).

Well, I figured, since I had the original Fuller transmission, I'd stay with the Fuller control knob. I hadn't thought about it, but I suppose you are corrct, though. There is probably a Mack knob that would do the same exact thing.

I wouldn't mind swapping out the medallion on the knob for a 10-speed shift pattern version. But, those medallions seem to cost almost as much as the knob! That is, IF you can even find them.

I wonder if there might be a Mack medalion to fit that Eaton-Fuller knob...

Oh, and I agree; those old round knobs are about as cool as you can get!

[rsb502]

I havent found the medallions with a pattern from anybody but eaton and no they arent cheap, Mack shifters are completely different so their cap wont fit it but Chrome shops have a relacement polished stainless one that you could have a bulldog engraved on for little of nothing Ill try to get a p/n and price tomorrow, I have a couple of them but they are long gone now. I got one and kept it in the package to have it engraved for a long time and never did it I finally just put it on like it was, they still look neat but a trophy shop should be able to engrave whatever you want on em, MACK script or a bulldog logo. or a shift pattern for that matter.

[Speed]

Hey, Speed.

The way this valve is ported is like this. When the range select lever is "down" (LO), the "supply" port is connected to the "delivery" port, which feeds the slave valve/cylinder. When the range select valve is "up" (HI), the "supply" port is closed-off, and the "delivery" port is exhausted to the atmosphere.

As long as your 2-speed valve is similarly ported, then I don't see why it wouldn't work. I mean, pressurized air and vacuum are similar systems. They both work on a pressure differential. The primary difference is the AMOUNT of pressure differential you have to work with. With pressurized air, you can get more work out of it. But, if the system is already functioning correctly on vacuum, then the cylinder sizes and mechanical devices are, by definition, already properly sized to do the work required. Remember, the control valve is just that; a CONTROL vavle. It doesn't do the actual work; the cylinders do.

So, as long as the porting works like I described above, it SHOULD work. If you are concerned about flow rates, and the associated time/speed of the system, you might consider using slightly larger lines. Mine are the original 1/8" lines. I believe most newer stuff uses larger 5/32" air lines. This will provide slightly more available "buffer" air, which should improve the function slightly.

The actual threads in the new valve are 1/16" NPT. So, this may somewhat limit both the maximum airflow through the fittings, and the variety of fittings available.

The original T-valve used 1/8" NPT fittings, just for the record.

The new valve works exactly as well as the original did on my truck. I can't tell any difference at all with the smaller fittings. But, again, the actual work is being done by the slave valve/cylinder. This valve just tells it what to do!

Hope this helps. Let me know if I can clarify (confuse?) the issue any further for you!

Kent

That makes perfect sense to me;the lines to the 2 speed are 1/2 inch vacuum hose(I think),but I can adapt that to the size the shifter uses easily enough. I might go ahead and splice into the lines somewhere downstream of my vacuum source,it's such a pain to disconnect the current switch in the dashboard. I think I can connect the "bat wing" switch elsewhere and see how it works;then if it turns out to be unworkable for some reason I can just disconnect it again and splice the Vac. hoses back together.

Thanks for your help on this.

Speed

[doubleclutchinweasel]

That makes perfect sense to me;the lines to the 2 speed are 1/2 inch vacuum hose(I think),but I can adapt that to the size the shifter uses easily enough. I might go ahead and splice into the lines somewhere downstream of my vacuum source,it's such a pain to disconnect the current switch in the dashboard. I think I can connect the "bat wing" switch elsewhere and see how it works;then if it turns out to be unworkable for some reason I can just disconnect it again and splice the Vac. hoses back together.

Thanks for your help on this.

Speed

excellent idea!