Red Horse

Like this-and I too would like to find a chrome one-at least the bonnet-at a reasonable price. Kind of hurts to pay 200 bucks for something made in china.

Just make sure you know for sure which version the spare six speed is. 107 has a useable hole gear- 1071 is a very low ratio (23.08)

That is kinda the point boys. If you followed the dash/visor plate, we wouldn't be having this conversation. As I said when I started this, young friend of mine has this beautiful R that he paid top dollar for. He has a guy driving it from time to time who thinks its a 7 speed-or even a 10 for that matter. I just want to be able to tell him..."don't let him drive it that way" if in fact he is doing damage.by the way-here is the truck-he let me use it for a few days for some "charity work" at our fairgrounds.

If my 2.68 reduction number is correct, then 2nd L (13.37) to 1st D (8.59) would be a 35.7% change. By the same token, 2nd L (13.37) to 2nd D (4.99) would be a 62.7% change-Not good! And again, we are talking 1071 here. Remember in my first post I said I used to pull 104,000 lbs with a 107? The 107 has a reduction of 14.10 in "L". Going from "L" to 1st "D" (8.59) is a 39% change. Very useable and doable. Thst same gear change in a 1071 is a 62.7 % split. Bottom line? Strictly an off road creeper gear.Bottom line- IF YOU ARE NOT DOING THE TRANS HARM BY RUNNING IN "L" IN ANYTHING BUT 1st- the 2nd L to 1st D gives you the best split. 35.7% Mr Harper says drive it by the book- its a six speed. I agree, but its like a 9 speed Road Ranger. which ever version yoiu have, are there 10 forward speeds? Yes. Is it safe to use the "mystery" gear? I don't know.

Rick, I'm with you but look at other responses. And the guy I referred to in my original post is not a "rookie" but an experienced owner. Do ypu agrtee with my "theory" in original post as to how ypou can calculate the ratios IF you are in LL with the stick in 2nd, 3rd, and 4th? Rob- You are making me feel bad. I used to occasionally drive an R tractor with a TRXL 107 (air shift) pulling 104,000 lbs (MA permits) and that transmission is truly useable as a 6 speed. But the 1071 with a 23.08 ratio in LL and an 8.59 in 1D??? I guess I'm just slow. LL is so low by the time you can complete the shift you -should I say "I" -have lost all momentum- and it won't go-and this is in a 10 wheeler at about 71,000 lbs.

LM, You are talking about a TRXL 107 right? Note-this is a 1071. There is no way you can get from LL (1st) to 1st direct without the truck coming to a stop. In a 107, LL is 14.10. In a 1071, its 23.08- at least I should say I cant!

With a bushel basket of money and a lot of time, anything is possible. Instead of bastardizing a Mack, if I had a good 3406 and a good 13 speed RR, I would find another Ford with a bad engine and swap it out- or any chassis that readily accepts the 3406. My biggest concern would be its not going to fit without a lot of mods and in any case, throw the radiator shell away because there is no way that stock radiator will cool that 3406.

I have a friend who has a very clean 88 R tandem dump (I think its a 688SX), big rears, and the 1071. He has a guy who drives it from time to time and the guy does not think its a six speed but rather uses the low hole air shift with the stick in other than first. As a matter of fact, he says he takes off with the splitter in "L" and the stick in 2nd. He then says he goes back to 1st "D", then second "D" etc. Any opinions? This harmful? As the chart for the 1071 says 1st LL is a 23.08 ratio and 1st "D" is a 8.59. When the splitter is in "D" is it a 1 to 1? And constantly driving the respective 5 speeds in the box? I made that assumption and dividing the 1st "D" ratio (8.59) into the LL ratio of 23.08, I come up with a reduction of 2.68. If that is so, then by starting in 2nd with the splitter in "LL" with a 2nd ratio of 4.59 I come up with a ratio of 13.37 (4.59x2.68). Am I correct? And again, and more importantly, is he doing this trans harm by running with the splitter in LL in anything but 1st.? Appreciate any education anyone can give me. And for the record, the spec sheet for the 1071 shows trhe followqing ratios: LL 23.08, 1st 8.59, 2nd 4.99, 3rd 2.84, 4th 1.66, 5th 1.00. Using my "theory" and if you used LL beyond 1st, you would have the following ratios: LL 23.08 1st D 8.59, 1st LL 23.02, 2nd D 4.99, 2nd LL 13.37, 3rd D 2.84, 3rd LL 7.61, 4th D 1.66, 4th LL 4.44, 5D 1.00

10-4 Rob- Thx guys

Guys, My B is 12 volt. I put a new Galion dump body on it and I want to replace my old frame mounted stop/tail lights (2) and turn signals with two new integral stop/tail/turn signals. Can I use LED's. Some people are telling me my flasher won't handle the LED's

rob- I'm afraid your skills (and energy) are way beyond this old boy! I'm really rethinking this issue now. If I compare gear ratios (ignoring the low hole) I find the following. What I did was pick the TRD720 ratios that came closest to the TRXL 1071 ratios Gear TRXL 1071 % change TRD 720 % change 1st 8.59 7.25 1L 2nd 4.99 42 4.16 2L 43 3rd 2.84 43 2.34 3L 44 4th 1.66 41 1.33 4L 43 5th 1.00 40 1.00 4H 25 .78 5H 22 Again, huge difference in rears as the 1071 would need a gear change to a 4.670 and the current ratio is 6.67 I'll try driving it this way with a load in a few days.

Thx Rob. I'm also brain dead as After I did the post I did a search on "cable clutch" and found that I raised this issue in 10/09, a few months after I bought the truck. I got some good info at the time-just never did anything with it. But my 6.67 rear has some play in it so I figured before I fool with that I should face the bigger issue. The original carrier is a CRD -62 and that was replaced with the CRD 118 in later versions of the RAD 111 axle. A 4.60 is the highest ratio you can get. Bob

Guys, From prior posts you might recall my B has a Maxidyne with a duplex (TRD-720) and a 6.67 rear. I can get a 4.60 chuck and a TRXL-1071. Has anyone put this 6 speed in their B? I gather I have an issue with the clutch right as the TRXL has cable actuation with a suspended pedal?

thx Larry- I think it was on "oldmacksrus" but now I can't open any of those info threads that the site has.

Guys, Anyone have the gear ratios for the TRD 720?

10-4 rob- I hear you

10-4 guys- thx- I have Duplex behind a Maxidyne in my 56, and everyone keeps telling me the back half won't take the torque of a 237 so I'm planing ahead.

Guys- Rob says .."air shifted." I'm talking about the one with two sticks- not the one with the air valve on the stick.

Guys, What is the proper nomenclature for the six speed TWO STICK-not air shift- that was used with 237 Maxidynes?

So what kind is that? (the snake, not the grouser!)

I believe you are correct-for sure its NOT a Euc. The ATHS mag of a few months ago had an article on Clines- don't have it handy but the reverse windshield appears to be a hallmark of Cline.

Name: Mack B-68X (1960) Date Added: 07 November 2008 - 06:21 PM Owner: Red Horse Short Description: Currently chassis View Vehicle

thx5thW- Maybe its a common to double reduction rears.

Guys, I was under my B-61X -it's a bit of an oddball, Duplex with a Maxidyne- and noticed that there is about a 1/4-1/3 turn/amount of play in the rear end. Its a CRD 62 with a 6.67 ratio. Truck does not "bang' or "clunk" but I was surprised to find that much play. Any opinions?

Fifth Wheel- Very nice job. I'm not sure I have the energy to do that. Like I said, I have a triangle-about an inch on a side that broke out. Short term I will tape it and maybe I'll try to do a fiberglass patch job for a long term solution.