terry

He is definetly going to have to match the rears with whatever tranny he goes with. Terry

The 2060,2070,and2080 all take a rear ratio of at least the low or mid 5.00 number, the 6 spd. really should be with a 3.86 to get any good road speed, and a 12 spd. overdrive and fuller work real good with a 4.17 ratio. terry

The one thing you have to remember is the 2060,2070, and 2080 trans take a different rear ratio than a fuller or a mack 6 or 12 spd. tranny. Terry

Yeah you don't see to many of them D models around, my boss has one he redone some years ago , and has two or three more stashed away in a building. Terry

They are different bell housing sizes, and i don,t think the frame is big enough for that engine. Terry

Where are you located? Terry

Should be some different dimensions on the front on length, i think the R700 had the longer hood, than the R600. terry

Ratios are as follows, 1st 14.44, 2nd 11.23, 3rd 8.59, 4th 6.68 5th 4.99, 6th 3.89, 7th 2.84, 8th 2.21, 9th 1.66, 10th 1.29, 11th 1.00 12th .78. And there are some 12 speeds that are just direct in 12th gear. Terry

are you looking for just a cab or whole truck? Terry

Would't they just be the block seriel numbers? terry

I beleive the macks were 50 55 and 60 inch spreads. terry

What do do with them trucks that 1999 trucks are needing frames and trunnion brackets? terry

I can promise you there was nothing staged about that picture, the company that i work for assisted the mover, we had a rubber tired loader pushing on the back of the locomotve. It was moved a few years back in Omaha. terry

I have a feeling that counter shaft is a lot looser than you realize, it might be one jumping around making the gears touch. terry

The only way i got the cotter pins in was to bend them in a curve and work them in, it is tough but can be done! Terry

When you get the nut and yoke off you can unbolt the rear cover and put the seal in on the bench, alot easier. when you slide the cover off there are two tapered bearings facing each other with a spacer in the middle, smaller spacers as the bearings wear down to set the preload. At the very most the rear bearing might slide off no problem, just be sure spacer is in there when you reassemble. Terry

That 400 E7 is a good engine, but be real careful of the V-8, parts are getting real scarce and real expensive. Terry

Have had loose exhaust seats do that at an idle or when you let off the throttle, might last a week or 5 years! Terry

If it was a gas job originally it will be pretty slow with a diesel in it if the rears have not ever been changed,also depends if the duplex is a direct or overdrive.Also the gas tranny is a smaller version of the diesel trans. Gas rear ends will be around a 7.00 ratio and a diesel can be mid 4.00 to down to high 5.00's or low 6.00's terry

Just take the 8 1/4 long one and cut it off to the right lenght. terry

The early 12 spd. had 2 sticks with the reverse, direct and overdrive on an air button on the main box stick, the other stick was just a lo-lo and direct box, it has a total of three boxes bolted together, a fairly long tranny. The later ones were the same just the lo-lo was a switch on the dash. It sounds like a complicated tranny but once you get on to it you will love it. When you are empty you can shift the main box all the way to 5th gear then go into overdrive on the air shifter,but if you are loaded then you just use the overdrive button for your upshift splits. first direct first overdrive,second direct second overdrive and so on but once your on to it you will know what gears to skip. terry

I am not sure on the no. of head bolts on which engine, but i do know of taking a thermodyne engine with the same no. of head bolts as the maxidyne, putting the fire ring liners in and scoring the head for the fire ring, and your good to go! terry

If you hear a rush of air then they lock up, it is the footvalve, just changed one on the R model i am driving. I have seen it before, always have been the footvalve. terry

AS far as i'm concerned the 1070 12 speed is the best trany mack has ever made! Terry