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My MH has an EM7 300 Maxidyne with T2050 transmission. I too would like a few more gears but I am learning to let it lug around 1200-1000 rpm and shifting at 1600-1800 rpm. I am only bobtailing so it does a good job pulling its own weight at low rpms.

Ken

PRR Country and Charter member of the "Mack Pack"

The current 6 speed Maxitorque transmission would probably not cause as many "between gears" problems as the 5 speeds did. The ratios are what they call "gathered", with a 40% split between 5th and 6th and the splits getting wider as you go down through the gears. So with a 2100 RPM governed speed you could downshift to 5th at 1500 and to 4th at around 1400 or so. I figured it out once and even with the smaller MP7 Maxidyne you could keep the engine above 1300 RPM even on a 6% grade at 80,000 pounds.

I don't know...Maybe I just got a bad batch of Maxie's back in 1987? but I bought 4 new R600's with 300 6speed's (2stick) 4.17 Mack rears Rayco sup. for pullin cement tankers. After the firest 75K it started with the Ambec inj pumps thay started to wipe out the inner bushings then I had to put a spare fan clutch in the trucks along with a set of belts, then there was the bushings in the water pumps!! So my Saturdays I was changin water pumps, belts an fan clutchs. So I said the hell with this so I went an bought a couple of Superliners with E6 350's an T2090 trans, 4.64 rears with the new Robert Bosch P7100 inj. pump!! no more pump trouble!! I instead started braking shifting forks in the 2090 an blowin up the trans an I do mean blowin up!! thats what happens when a trans gets stuck between 2 gears!! Now after the 2'nd trans. Mack tells me that they make a new shifting cover with heavier forks an rails!! OK that's nice but what about the first 2? well anyway Mack never stepped up to the plate for any of the above. I now own F-Liners Classic's With Detroits an I have yet to have an issue with warranty an even when is over they still give me some help. Maybe Mack has gotten better? But I del. to a lot of concrete co's in the NY Metro that used to be 100% Mack an are now Western Star an front discharge mixers! the drivers I talk to don't much like the front loaders (cab is to small) but they like both W-Star an Mack for driver comfort an handling.

Ernie DS

Yea Mack lost a lot of sales in the 90s to other truck mfg due to poor warranty standards and limited truck models.

The 12 speed was imo the best trans for a maxidyne.like you said...drive it like a 5 speed empty or split the last 2 holes when loaded. It had overdrive in 5th hi, or that deep deep reduction in that low hole gear on the dash switch... only thing that was a problem was the range selector clutch packs..always let the feats grind.

Yea Mack lost a lot of sales in the 90s to other truck mfg due to poor warranty standards and limited truck models.

The 12 speed was imo the best trans for a maxidyne.like you said...drive it like a 5 speed empty or split the last 2 holes when loaded. It had overdrive in 5th hi, or that deep deep reduction in that low hole gear on the dash switch... only thing that was a problem was the range selector clutch packs..always let the feats grind.

Lmack,

I never had a 12 speed; but have heard nothing but good things about them!! I also know of a few guys up my way who took out the 2090's an changed the bellhousing an put 8LL Fullers in there Macks

Ernie DS

I don't know...Maybe I just got a bad batch of Maxie's back in 1987? but I bought 4 new R600's with 300 6speed's (2stick) 4.17 Mack rears Rayco sup. for pullin cement tankers. After the firest 75K it started with the Ambec inj pumps thay started to wipe out the inner bushings then I had to put a spare fan clutch in the trucks along with a set of belts, then there was the bushings in the water pumps!! So my Saturdays I was changin water pumps, belts an fan clutchs. So I said the hell with this so I went an bought a couple of Superliners with E6 350's an T2090 trans, 4.64 rears with the new Robert Bosch P7100 inj. pump!! no more pump trouble!! I instead started braking shifting forks in the 2090 an blowin up the trans an I do mean blowin up!! thats what happens when a trans gets stuck between 2 gears!! Now after the 2'nd trans. Mack tells me that they make a new shifting cover with heavier forks an rails!! OK that's nice but what about the first 2? well anyway Mack never stepped up to the plate for any of the above. I now own F-Liners Classic's With Detroits an I have yet to have an issue with warranty an even when is over they still give me some help. Maybe Mack has gotten better? But I del. to a lot of concrete co's in the NY Metro that used to be 100% Mack an are now Western Star an front discharge mixers! the drivers I talk to don't much like the front loaders (cab is to small) but they like both W-Star an Mack for driver comfort an handling.

Ernie DS

thats very interesting,,glad you found what you need,unfortunate about the warrenty,i had pretty good luck with warrenty 20 years ago...seeya bob

thats very interesting,,glad you found what you need,unfortunate about the warrenty,i had pretty good luck with warrenty 20 years ago...seeya bob

Gary W Gray Trucking out of Delaware NJ ran a fleet of about 50 or 60 R's an 427 CH'S 100% Mack.. Today? not a one,he had the same prob. Mack left him hi & dry back in the late 90's so it wasn't just me... But it looks like Mack has got there act together? seems like there sellin a lot of trucks,an thats a good thing!!

Ernie DS

ya thats not cool at all,ive been out of macks for 21 years now,used to be an owner op,,company driver now,,,but thats not good business at all.we run cummins,in our kenworths,they seem to be unbreakable.only petty electric switch problems.what i didnt like mostly,about mack,at least here,was those dam fuel lines exploding,leaving you strandid in the middle of nowhere,nearest parts like 300 mile from where you are,and i usually had to tow it.ca ching ca ching.just for a dumb fuel line nobody had,rite?...bob

  • 5 years later...

Nice Macks you've been drivin' there, mate! Here in the USA Maxidyne engine ratings are still available, but the wide ratio transmissions to match them pretty much ain't. However, Mack's website says something similar to the old Maxidyne/5 speed Maxitorque is still available, in the form of the 395 HP MP7 Econodyne with the T306 gathered ratio transmission.  IMHO this would make a cool old school powertrain for on highway use at our low (36 ton) U.S. weight limits- You'd need only 5 gears to go from a stop to freeway cruise speed, yet with the 40% split between the top two gears you wouldn't have the engine screaming and wasting fuel before you could upshift like the old 5 speeds did. Pair that with the current Mack air lift pusher for a 6 by 2 bogie and you'd have a heck of a lightweight, high efficiency combination... But of course, they'll only let you have the factory air lift pusher setup with the fragile Volvo automated manual transmission. 'Spose you could just buy the tractor as a 4 by 2 and DIY the pusher axle, but then you may as well buy a glider from Daimler or Paccar and really do it up right!

  • Like 1

I pulled into a job last week with a 1978 DM triaxle the super ask if it was late 80s no his company use to by macks 20-30 a year the last batch mack had to change all the frames on the CLs now they went to Kenwoths and not lookin back between the two company's they have 200 plus rolloffs triaxle dumps and tractors.

Ed

My 2 cents worth sez:

Mack iz bomb proof 

we had a cool power 300 with a 2 stik 6 speed ..... we din kno how it twould handle Heavy Haul

= No Worries only problem U tend to cum off hills in tooo higher gears n burn the brakes just need th@ in between gear

n drive n the 6 speed twaz the next best thing to an automatic az U did half the gear changes th@ U do with a screemer n RR

we used the engine brake to kill the revs Between gears n U were able to pull the lever straight thru with no time for a cig

With Mack we luvz the multi speed reverse az U can shift m on the run 

LOL

 

cya

§wishy

  • Like 2
18 hours ago, blackdog2 said:

I pulled into a job last week with a 1978 DM triaxle the super ask if it was late 80s no his company use to by macks 20-30 a year the last batch mack had to change all the frames on the CLs now they went to Kenwoths and not lookin back between the two company's they have 200 plus rolloffs triaxle dumps and tractors.

Seems strange breaking frames in CL. They are a rugged truck must of been spec'd wrong . We had 3 CL  log trucks with 600k to 700k miles and the frames were all still good 

The log chassis are heavier spec frames but some choose to go that route for dumps it all comes down to $$$$$$.  Back in the 80s I work for a large rigging company that had 150 tractors 99% Macks and we did things you wouldn't believe what we move around New England they wasn't the fastest but no accidents

Ed

9

3 hours ago, blackdog2 said:

The log chassis are heavier spec frames but some choose to go that route for dumps it all comes down to $$$$$$.  Back in the 80s I work for a large rigging company that had 150 tractors 99% Macks and we did things you wouldn't believe what we move around New England they wasn't the fastest but no accidents

The frame is the worst place to try to save money .  To me your better off making your truck a little heavier and a little bit more expensive  and know it's gonna hold up.  Yeah when I was a kid here in western new England mack was the leader in construction, heavy haul ,forestry . Things have certainly changed. 

On 31 mai 2016 at 0:35 PM, logtruckman said:

9

The frame is the worst place to try to save money .  To me your better off making your truck a little heavier and a little bit more expensive  and know it's gonna hold up.  Yeah when I was a kid here in western new England mack was the leader in construction, heavy haul ,forestry . Things have certainly changed. 

The crossmember behind the cab on the CL's with double frames were a common and constant problem up here. 

Mack never did come up with a better crossmember they would just be replaced one after another. 

Seemed as if the frame was rigid as heck on the back side but up near the cab it was the weak link in the chain. Dump guys had it the worst as some hoist cylinders were mounted very close to the failed cross member. CL was commonly used up here for tri axle dump trucks through the 90's. 

We never broke a crossmember on a CL . They were straight trucks 265 wheelbase loader on back . Severe off road use . 700k miles I have heard of that crossmember issue luckily we didn't have thato issue . There was quite a few CL log trucks in new England from 94 to 01 most were replaced with brand x trucks when traded . We liked ours they were just as good as the superliners we had 

I broke one behind cab crossmember. Then the parts guy said you can get severe duty ones. After that never an issue. Most parts guys never heard of the severe duty ones or they're to lazy to do the research. 

On June 4, 2016 at 1:54 AM, Dirtymilkman said:

I broke one behind cab crossmember. Then the parts guy said you can get severe duty ones. After that never an issue. Most parts guys never heard of the severe duty ones or they're to lazy to do the research. 

That's odd to hear. But no doubt the boys at Watts would steer you in the right direction.

The former Mack Trucks had a service bulletin on the retrofit of the severe duty crossmembers (e.g. 9QL4551M and M8 variants). We sold thousands, and I never saw one of these replacement crossmembers fail.

  • 3 months later...

I have a 03 RD, I recently had my local Mack Dealer change software and turbo to the AMI 370 

wow what a diderence she pulls from about 1200 to 2150 every gear. It has the Eaton 8LL and 4:42 gears and 24.5 tires.

is there a transmission that would be better suited for this combo ?

i really like the idea of the 5 speeds used in the 70's and 80's !!

although my 4:42 ratio wouldn't work so well with that trans

Edited by 03' Big Red

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