Vladislav

Wow! That thing catches an eye for a while. And the interior bets the outside look even together with that Finish fall forest background. From the pic I see the truck has white sidewalls on the tires. Wonder what are they? Paint?

Seems like the kind of things when a good one takes you out of what you like to do

Roamed around two transmissions today thinking of a mistery of air switch connections and the need of shortening the prop shaft. And after reading T2090/T2090 repair manual (fortunately I've got it but to my stupidity haven't bought one of T2060/T2070/T2080) a feeling appeared that it's possible to re-install the compaund housing off the 9-speed to the main body of T2070. Making some math it turns out that you get a set of ratios T2080 8-speed unit has keeping sinchronized hi-lo shift with the 9-speed rear end. Not 100% sure since some Mack-designed "surprizes" might be found such as modified splines on the front main shaft where the main compound gear attaches or different shift forks on the main top cover I'm going to re-install too keeping air shift unit but seems it worth making a try. Going to wash away some grease off the body (transmission's, not mine) and turn wrenches a bit tomorrow. Will share the results.

Sean, Unfortunately I had no trolley handy this time. Would help much. But a cabover is almost another story. I'd just go with a overhead hoist I use to equip every shop I build (the score is 5 to the moment). Having a conventional I got to an idea I'd even remove the cab if the truck has no sleeper. My original plan was to get the engine out together with the tranny but I found no good spots to hook it up. Had nothing of lust to turn head bolts for attachments as Mack prescribes. Hmm.. Towing the bus forward.. My hat's off to you about that, no doubt. And after a bit of scratching my head it looks to me I also could block Mack engine and move the truck backwards with its front crossmember and bumper removed. Ok, always something for a next time

That pit looks deeeeep!

Happy Birthday! Sometimes it gets on my mind that the best present for you would be a set of drive tyres

Ok, looks like it needs twice less travel of a tranny backwards. I had to move it for nearly 15 cm /6 inch to get the pinion out. On the other hand the side mounting brackets were ready to pass the chassis supports about the same time. I will be Ok if put the unit back with no brackets but seems like the same long amount of travel is required for the remove. There's a point that R-model brackets (twin rubber pads) are wider (longer along a frame rail) than ones on MH or Superliner. So that issue wouldn't show up working on those models. Thanks the great for guiding me up.

What also surprized me is the pulling type of the pressure plate. All cars I dealt with and even my Mack of 1945 had plates a bearing presses on toward the flywheel. You probably can't do your trick with that style so I just kept it out of mind.

Thanks, just didn't know it's possible that way. Seems also preventing from getting bent anything in clutch while tranny hangs on its input shaft.

The air lines on T2070 look this way. As you can see some of the connections have no attachments and I don't have knowledge of what to attach to.

Hi all, Finally got myself into an entertainment I was going (and avoiding) for a while. Found some troubles and hope finding useful tips. So the help is appreciated. The truck is 1988 R688ST E6-350 4V Econodyne with T2090 9speed and 5.02 Mack rears. It's for a hobby and no trailer in distant plans. The reason to go from one tranny to the other is 1st the original one is worn bad, 2nd I could locate a good 7 speed locally, 3rd 7 speed provides higher top hole of 0.60 instead of 0.71 with 9 speed. Also jumping wider steps I hope to drive easier in the city traffic I use to get in all over my place. Not sure all that will be perfect but I'm not prohibited from putting 9 speed back on in the future since total chassis rebuild is on the list. Will need a rebuild and faster rears in that case. To the moment I took off the original gearbox from the engine and got it on the ground. Had to remove left side fuel tank, big air tank, cab floor and a shift lever. Jacked up the engine a little to get the rear mounting brackets elevated from the pads to be able to remove the tranny. Placed wooden blocks below the engine flywheel housing and than started working with the tranny using the jack and blocks.A trouble was found to get it rearwards enough to clear up the spigot off the clutch bearing since the rear end of the transmission took against the rear cab support bracket. So finally I had to lower the rear end and move it slightly leaning against the crank shaft line what I disliked to do. The unit to go in is even longer having larger compound housing desingned for multi-speed PTO (which I have no need in) so seems the things will be more cantenckerous for re-installation. Current idea is to remove the mounting brackets from the transmission housing and try to put it back slightly biased to the fllor at the rear. But maybe some other options exist? Also there's a question which might be found as a dumb one. I took the unit off keeping the clutch assembly on the flywheel, the way I always do on cars. But it looked like I also could remove the pressure plate mounting screws through the lower opening and get the tranny together with the clutch. Which way is correct? And what is more important, which one to put it back? The next issue is I don't have an air schematic for T2070. The pipe connections I have on the unit are different than T2090 has. And they are not complete. Additional trouble is the shift knob on the 7 speed is ruined and I'd like to keep the 9 speed up and down flipper. But it has 2 lines only and the 7 speed one has them 3 or 4. Have no idea of how to make it working the 1st insted of the 2nd and if it's possible at all. As a retreat option I have a shifting knob off T2080B with a revolver style flipper, the same kind as used on TRTXL1070 12 speed. Might work the deal out using that part if knowing how to appange the lines. Some pics attached below. Thanks in advance for advices and any thoughts on the matter. Vlad

Best B-day wishes!

It's not so complicated in an old rig. You do it once well and it works good for a decade or more.

Is there a piece of a middle of nowhere anywhere in PA? i thought you guys are tight neighbouring to each other there.

Mike, we all keep you in mind. Hope this would help you climbing uphill at least a lil bit.

Looks in a very nice shape for a STEEL DASH F-model

Not a breed truck on my mind but looks good sometimes when painted right. And in your particular case it has a history. Here's a pic of one in Russia from a bunch purchased by some beef and pork producing facility out of Saint-Petersburg. They bought 10 or so units in 90's and later sold them off to different owners. Some one shows up for sale from time to time. They don't use to be cheap having fridge body on but affordable if I really wanted. So i had similar thoughts of that crazy kind a couple of times as you do now. Could stop myself knowing I was limited with a potential of attention to any extra project.

T2070 (and T2080,T2060,T2050) all have the overdrive of 0.60 Mack T2090 9 speed which would work the way you want has the top notch of 0.71. The same with T2100 10 speed whicj is quite similar to T2090. Knowing your drive axle ratio and doing the count you will learn how your maximum speed or an actual spped at some particular revs would drop. Going from T2070 to T2090 you will have 0.6/0.71=0.85 of your current speed. For example if you do 60mph with some revs now you will be at 60x0.85 = 51mph. Another point T2070 were in two sizes of the housing (and many other T200 series boxes too). T2090 was always in the short bow and T2070 usually (or always?) in the long. So prop shaft modifying would be required. Currently I'm close to the moment of swapping T2090 with T2070 in my R688. So catched some facts over them both. But I'm not with a done deal yet. Sure some other options such as Fuller etc could be applied but I'm not familiar with those trannies.

Quite interesting. Indeed there were EM7s so EM6-4V should be as the predecessors too. On a side note were any DMM's assembled at Oakwille?

Wow! Thank you for the lesson. The thing that messed me up was I thought 250, 275 and 300hp versions were only 2 valvers.

I noted that too. But it appeared to me he quoted from time to time recently.

Interesting color combo.

I wish it will get better soon. At least for a fishing rod for the beginning.

Amazing! I like it too much. Did you use some Italery parts for 1:24 one?

Wow! 23 Birthday girls folks!