dieselrob

Were looking for a mid 80s r model. And we have been all over, just got back from cleveland 5.5hr ride. Just cant find any with the right tranny, air select. There is one with a 5 speed no spliter, anyone know if they can perform like one with a maxi tourqe 9 speed? Not looking for speed, but just abality to haul, or tow trailer and excavator 18 ton and smaller stuff. Its 300 hp em6, 18fr, 44r, 14ft dump 42 inch sides and the 5 speed.

RickG

I ran an R Model with 5 speed hauling corrugated in a 48' trailer . It'll pull fine , just takes longer to get up to speed .

dieselrob

What about in the mountains and such? We lost one a few weeks ago over side of the bank comin down the mountain. Only cuts and bruises. The trucks saveable, but it has a 9 speed maxi and i was thinking about a swap if the 5 speed is no good for hauling.

Pentastar

Usually the 5 speeds with that combination of drive train are road tractors and as you already know will not start a dead pull without damage to the clutch etc.You need the low range for a dump/lowbed application.Mack made a great truck back in those days,it looks like the new stuff is junk.Sad.Ron G

Totallyrad

I have an 85 with the 9 speed I use for my pull tractor. I also pull 35k excavator and smaller equipment. I like the low hole on the 9 plus the extra gears, no issues on the hills.

058hamer

Id look for a rd with a 12 speed maxi tourqe in it I low bed with a 9sp and with a rr trany i like the rr beter i lerned in 671 2strokes but we have a few mt 12sp alot beter than the 9sp i think 058hamer

dieselrob

We cant find one with 100% of what we need. If its in our price range and size range its always missing one thing, no jake, un preferred trans, or not the right hp range. Hp and jake are more important than trans tho due to mounatins here. All the places with trucks sell them to buyers in nigeria with in 2 days of it being there. There is nothing within 600 miles that we can find advertisement for. The truck we recked is gonna be rebuilt by spring, so this is just to get threw the winter. If we dont get that back together we can swap the 9 speed out, and whould be good.

tiebox

I have (1) 85 686ST, 300, double frame, 5 spd with the 2nd stick to select range LO, DIRECT or REVERSE this tractor will pull 80,000 no problem just a little slow out of the hole.
Its used to move equipt, or pull a 24ft steel trailer loaded down with wood, dirt, stone or concrete.
I think the most we went across the scales with was 83,600 .
Fronts are 14K, rears are 44K, don't recall the ratio off hand, it runs 60MPH flat out on the highway loaded, 65 empty.
Only use LO 1 in the pits/quarrys or dumps or when stuck in the muck on a job site and in those cases the driver just lets it walk it self out.
We are here in the midwest and stay local so not many steep grades.
The tranny is pretty much bullet/ proof.
Its all Mack.

dieselrob

Ya we have an 86 with the 6 sp low hole. I love that one, fun to drive. There was 2 in ohio that we would have bought instantly with that trans but after the guy said drive them and check them out, he comes back with the paper work and says well it was never marked down but they were sold to the out fit in nigeria 2 days ago. So the only one left that was what we wanted had the 5 speed.

bandit1trucking

I've got a '80 Mack R-600, 300Maxidyne, 6 speed that we've honestly grossed 155,000 pounds with (Koehring 666d excavator...the whole thing...), and regularly grossed from 94,000 to 115,000 with 2 other excavators. Kinda slow starting out, but not real bad considering the lack of gears. Not real sure of the rear end gears, but on 11:00 R20 tires, at 2,450 rpm's (it's turned up just a little) it'll run right between 75 and 80. Back in the early 80's, when it was pretty new, it wasn't uncommon for this truck to out-pull trucks with 400 cummins and 425 cat engines on some of the local hills, and I also had 2 '79 models that were the same powertrain, and run comparable. I will say, DO NOT get one with the 237 Mack. They're tough, dependable engines, but gutless wonders...

dieselrob

If it wasnt 300 we walked away instantly.

Ground Shaker

If your looking for a certain truck call up 4state, they will probably have one. We got 2 Kenworths from them back over the summer. Rebuilt them a little and love them now.

dieselcarpenter

I have heard that MACK's are hard and expensive to get parts for, and also hard to work on is this true???

Totallyrad

I don't know if they're any harder to work on than others but Mack has a great parts support system. They've always had or could get anything I've needed and mine is 22 years old.

cheapskate

my ol' man just got an '85 econodyne with the 9-speed and the 300 e-6. he doesn't even know why he bought it. its a single axle, though so not much good for heavy loads.