8LL advice-Thanks

[BR83]

Thanks for the advice on the 8LL guys. I have now driven it but the guy who showed me how to drive it told me to split every gear-you have a low gear and then 1-4, you start in low gear with the selector in low when ready to shift you move the selector to the D position and let of the gas. When you hit the gas again it shifts to low gear in the D mode. Then you go to first gear in the low position. You use this pattern all the way up to 4th gear in the D position. When downshifting from the high end of one gear to the low end you just move the selector to L and press and release the clutch. This takes some practice to get the hang of but once you do it isn't as complicated as it sounds. I have not tried driving like a straight 8 speed like you said. I am not sure if this particular model can be driven that way or not but I will find out and let you know. Thanks again.

 

[kamerad47]

This is not a 8spd LL!! it this a mack trans??? they made some of these junks in the 80's !!! are you sure this is not a 12spd mack they made them like that??

 

[Steve Frazier]

You're not talking about the RoadRanger then. Take a look for that shifting diagram I mentioned, it will list what tranny this truck has. It does sound like a Mack transmission, not Eaton/Fuller.

 

[RonG]

I thought that his description sounded like a Mack transmission when I first read his post but since I cannot be there to see it you tend to assume he knows what he is talking about.
I generally would not worry too much about splitting gears until you make the change to high range unless you are pulling pretty hard,especially if your engine brake works properly.
I think that the high torque rise engines of that era were basically Maxidynes and the Maxidyne over the road versions did it all with a 5 speed which tended to create big smile among the drivers raised on 15 and 20 speed Triplexes and Quadruplexes. :slomo Ron G

 

[BR83]

8ll

Now that I have been driving this transmission on the job I thought I would let you know how I have been driving it. First off let me tell you that it is a Mack, or at least it is in a Mack. The truck is an '87 Mack tri-axle dump truck (Rw 713 model). There is not a shift diagram in the truck or anything that says exactly what the tranny is, but I was told it was an 8LL. However, it is not an 8 speed driven by spliting at 4th gear (like a repeat H pattern). This particular transmission is driven by splitting every gear when there is a load on. Empty it can be driven in high range only. The shift pattern is like this:

X 1 3
L 2 4 The splitter button is like this: D-L] N-R

When driving it with all of the gears it is started in low gear (L) with the splitter in L. When ready to shift you move the splitter to D, let of the gas pedal and then press the gas again, you are now in low gear D mode. The next shift is to 1st gear (1) in L mode. To do this you move the splitter to L and double clutch to 1st gear. This pattern is repeated up to 4th gear in D mode. To downshift from D mode of a gear to L mode of a gear you just move the splitter, let off the gas, press and release the clutch, and then press the gas again. To go from L mode of a gear to D mode of the next lower gear you just move the splitter and double clutch like a normal downshift. Like I said before it takes some practice because it is definitely not a typical transmission but once you drive it for a while it is easy. Explaining it makes it sound harder than it really is. Thanks for all the comments.

 

[digger242j]

Is this all taking place in the tranny, or is it a 5 speed trans and a 2 speed rear end? Because, what you've just described is essentially how you'd drive a 5 and 2.

{Digger thinks a little more, and what he's read eventually sinks into his thick skull...}

Oh! Ok. Dumb question, because if it's a triaxle you're going to have two rear ends...

So, is it all in one big gearbox, or is it a main gearbox and an auxilliary?

 

[BKrois]

Sounds like a mack 10 spd?

 

[Steve Frazier]

I'm pretty sure it's a Mack transmission, I drove a tractor with this one in it. Everything takes place within the tranny. L = Low, D = Direct. If I remember right, there's a splitter on the tail end of the transmission that acts just like a 2 speed rear.

 

[kamerad47]

It is a mack 12spd!!!

 

[digger242j]

It is a mack 12spd!!!

Then I'm confused.

How does L + 1st, 2nd, 3rd, and 4th, (that adds up to 5), multiplied by "L" and "D" (that adds up to 2), equal 12 speeds?

 

[BKrois]

If the truck does have a mack 12 spd, it will either have a lo hole stick, or an air operated switch on the dash for lo hole. If it doesn't have that, it is a mack 10 speed. I looked in my friends tractor before which has a mack 12 spd, and it has the knob with D-L-N-R on the splitter, along with the air operated lo hole switch.

 

[Cat420]

Then I'm confused.

How does L + 1st, 2nd, 3rd, and 4th, (that adds up to 5), multiplied by "L" and "D" (that adds up to 2), equal 12 speeds?

Plus L" and "D" reverse should equal 12. Don't some speed designations(8, 10, 12, 13 etc.) take reverse into account? That's the only thing that I can think of.

 

[Steve Frazier]

No, a tranny is designated by it's forward gears. The transmission we're discussing here has 5 speeds in reverse. You can get going almost 30 mph in reverse!!