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Discussion Starter #1
Been keeping my eye open for a truck for a few years now to put the box onto from our old Bruin. It needs to have a long frame as it's a 22 foot box. Came across a '94 Mack RD688 I believe it is the other day. Has the E7 @ 350 horse, 4.64 rears, 18,000 front axle and 44,000 rears. Looks to be in decent shape, few little things but nothing I can see too bad. No oil leaks anywhere. Biggest question I guess is about the transmission. It has a 12 speed air shift. What are they like? Just has the one shift lever, not 2 like some did. Never drove one like this before, might give it a test drive next week. It's no Cadillac by any means, rugged work horse, completely mechanical. Just going to be for a second truck/backup/yard truck. Anyone have one or used one before? Not sure the actual hours or miles, but sounds like it had a somewhat easy life as a potable water hauler for a camp out west then a construction company in Manitoba bought it thinking it was for spreading water on jobs sites so never used it. Whether that's the truth, I can't confirm.
 

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Cousin bought one new and loved it, i understand its a five speed with a deep low and every gear splits. Also have reverse in every gear.
 

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Was one of three that maintained and kept a 32 truck fleet of 1980-1998 vintage 600 series Macks running in the Alberta patch for seven years...can tell you pretty much anything about them you want to know.

They are tough, kind of crude in some aspects, but will take more **** and abuse than pretty much anything else out there. I'd buy one no question except I have issues sitting in them for extended periods due to leg room, the cab is not really made for tall people. Relocating the seat so you can jam it up against the back of the cab helps.

Not sure if its still there or not, but we actually donated a twisted input shaft that Nait used to have on display, thats how tough that 12 speed is.
Many driver issues we run into regarding power complaints and more were direct result of the truck not being driven "as a Mack". They need to be wound out and shifted properly to produce power. Once you learn how that tranny shifts, its actually quite simple. The two sticks was an option for low range, normally everything was all done with the one. Reverse is shifted into by selecting it with the knob. PTO is run by selecting the neutral position and then selecting a gear suitable for whatever speed you require. Some had the PTO run off the rear of the counter shaft for high HP.

IMO biggest area of concern with the driveline is the peanuts in the power divider, its normally what fails when they let go, but usually it is due to wear from high usage.

Different suspensions were available, standard was camel back, if components are wore, some axle alignment issues can result and you will get a lot of clunking and banging while driving especially when empty, caused by slop in the spring caps where they bolt to the housings or the trunnion bushings also. Torque arm bushings are another high wear point.

Check the frame rails for a few feet behind cab for cracks along withe ends of the mid frame crossmembers. Also in the suspension area where torque arms attach. Also a sign of how hard its been rode, check the lower front of the cab behind the engine in the middle for cracks in the sheet metal, also check if the dash frame is all tight. Hood hinges are another telltale area.

If you want to run in in winter, you need an auxiliary heater, but most have had that already installed by this time.
 

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Discussion Starter #5
I'm 6'2". When I sat in it there seemed to be a fair bit of room. If you have ever sat in a GMC Bruin with a Detroit, anything would seem to have lots of room! Whoever designed the Bruins must have had skinny feet, only one leg, and no neck.
 

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I'm 6'2". When I sat in it there seemed to be a fair bit of room. If you have ever sat in a GMC Bruin with a Detroit, anything would seem to have lots of room! Whoever designed the Bruins must have had skinny feet, only one leg, and no neck.
We have a brigadier.....they were likely only 5’ 2” also. I have drove a few old Mack’s and they are like a Cadillac compared to them.
 

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Discussion Starter #7
We have a brigadier.....they were likely only 5’ 2” also. I have drove a few old Mack’s and they are like a Cadillac compared to them.

Perfect! So you are probably looking for a good, used parts truck!!!! '81 GMC Bruin 8v71 Detroit, 8 of the 10 tires hold air, no rust what so ever anywhere near the motor as it has a healthy coat of oil, comes with a box of old style fuel cartridges and box of ear plugs. No box.
 

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Discussion Starter #11
Thinking we will go take a look at it Tuesday and for a spin. Will likely buy it, price is certainly right. Has a wet kit and long frame so will just have to slap the box on and hook things up. Won't be as nice as our 95 Kenworth, but will do what we need it to.
 

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Knew a guy with six R600 on-farm haulers pulling 30 ft tandems.
Great trucks for the job.
Like anything secondhand, maintenance history is paramount.
 

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We picked up an 87 model about 6 years ago for $1000. It’s got a hotted up E6 350 with 9 speed. Only mechanical thing I’ve had to touch was the hi/lo pistons in the box, it’d been a yard truck for a long time and never been out of low. Electrics have been expensive but that’s what happens when you let the wrong people touch stuff.
 

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Discussion Starter #14
A Thousand bucks???!!!! Good buy!!!!! Something about that style of Mack I really like, The one I'm looking at has the newer style hood. Sweetest truck I ever seen was a Mack Superliner that the guy had all done up, I was working construction then and the guy gave me a ride from the pit to get my half ton, was really nice in the cab, smooth and quiet. Since then I have always wanted one of those for a grain truck, just do it up real nice, mostly for show.
 

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Hard to beat a late '80's Mack Superliner with an E9 and 12 spd splitter.
They are one tough truck!

In 1988, Mack Trucks Australia made 16 special edition Super-Liner II Bicentennials with the E9-500 V8, Mack 12-speed triple countershaft transmission, Mack front and rear axles, long taper-leaf springs on front and camelbacks on rear, Spicer 1810 HD driveshafts and a 5842mm (230 inch) wheelbase. The special limited edition models were named after people influential to Australian history, including James Cook, Captain Bligh, Ludwig Leichhardt, Governor Phillip, Ned Kelly, Kingsford Smith, and John Flynn William Hovell.



Truck Specifications

Engine:

•E9-500; 375kW (500hp) @ 1900rpm.
•2173 Nm (1603lbstf) @ 1350rpm.
•Mack turbocharged and after cooled V8 diesel with four valves per cylinder.


Transmission:
•Mack triple countershaft manual overdrive 12 speed transmission with ratios to match application.
•High torque rating of 2305Nm (1700lbsft).


Driveshaft:
•Spicer 1810 Heavy Duty Series drivelines.


Front Axle:
•Mack FAW538C 6,500kg (14,300lbs) capacity.)


Rear Axle:
•Mack SSB38C 17,252kg (38,000lb) or Mack SS441C 19.976kg (44,000lb) bogies both with single point suspension and 1400mm (55in) spacing.
•Rear axle ratios range from 3.87 to 5.73.


Frame:
•High tensile, pressed, heat treated alloy steel 228mm (9in) double frame.
•Each 228mm (9in) double rail has a resisting bending moment of 208,000Nm (1,840,000lbsin) Weight per millimetre in 25.2g (1.4lb/in).
•Body bound bolts on major chassis members.
•Turntable angles fitted.
•Frame mounted tow pins.


Wheelbase:
•5842 (230ins).


Fuel Capacity:
•Round polished aluminium tanks with vehicle capacity of 2000 litres – 4 x 500 litre tanks.
 

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I’ve got a soft spot for the Superliner Mack’s. Used to use them hauling logs turned up to 700hp+ which was a lot back in the day.

Like mentioned a few times in the thread I pretty much can’t stand driving them any more. I think our CL713 even has less leg room than the superliner’s.
 

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We have a few Mack’s around, (grandpa used to be a dealer). The 12 speed air shift is arguably the toughest transmission Mack ever built, just make sure you clean all the shifter parts up and change the filter on the tranny and it will work well, it’s actually a 10 speed with a deep reduction for 1st gear that is a switch on the dash in your case, you most likely won’t use it much. The E7 is a good engine, 94 will probably have some electronics on it called the VMAC system, a 350 won’t have a lot of power if you are expecting to get out and run down the road 70mph with a full load you might be a bit disappointed (E6 350 will outpull an E7 any day of the week). Overall everything has already been said in this thread. Oh, here is our Superliner we are fixing up, grandpa sold it New to the previous owner back in the day.
 

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Discussion Starter #20
Took it for a little test drive today. Seems good and solid, few minor fixes would be needed, nothing major we noticed. Transmission would take some getting used to, have drove mostly 13's and the odd 10. Does anyone know if there is an updated shifter knob for these 12 speeds? Seems somewhat cumbersome with the shift buttons on the right hand side of the knob, must be made for you Aussies! Doesn't turn real sharp, but not any worse I don't think than the old Bruin. Forgot to look at the front tire sizes, has the big wide ones, what do they cost to replace? Looks like they should pass a safety.
 
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