New Granite Review

[Bullheaded]

Last week I got bored one day at the mine and parked my loader and jumped in a new Granite dump truck because I wanted to try one with the M-Drive auto.

Lets start with the truck. We had some rental Peterbilts and T880's and they started falling apart so we brought these Mack's in and they have been taking the punishment. They are running 30 KM round trip loaded with 25 to 30 tonne of ore on horrible pot holed washboard. 

I can say, they ride incredibly good, especially considering these ones have rubber block rear suspension. They ride every bit as good as last truck I used to run, a loaded air ride 2020 4900 Western Star. And no squeaks or rattles. Pretty impressed with the truck itself.

Now the M-Drive auto. They might be good on road, but not my thing off road on hills that are shown as 15% on the dash displays in our Cat rock trucks. Actually panicked me a few times because they feel like they go in to neutral between shifts there is such a long pause. And I spun out on one hill because it decided to shift (and pause) right at the peak of the hill. Yes I know I could have used manual mode, but wanted to see how they did in auto. I did not like at all.

But then I tried performance mode and performance plus and they performed a lot better. But in this application of big hills and having to slow constantly to almost a stop for giant potholes, they seem to get confused and shift way more than necessary. The MP8 505 has plenty of power to pull a gear but they would still shift down.

Not my cup of tea, I'll take a manual any day. But they might be nice for use in town or for idling along with a roto-mill.

Engine brake was pretty strong too, compared to Mack's of old.

[mowerman]

Thanks for that my Peterbilt automatic used to do the same thing do screwy things when you get down to very slow speeds… bob

[Red Horse]

8 hours ago, Bullheaded said:

Last week I got bored one day at the mine and parked my loader and jumped in a new Granite dump truck because I wanted to try one with the M-Drive auto.

Lets start with the truck. We had some rental Peterbilts and T880's and they started falling apart so we brought these Mack's in and they have been taking the punishment. They are running 30 KM round trip loaded with 25 to 30 tonne of ore on horrible pot holed washboard. 

I can say, they ride incredibly good, especially considering these ones have rubber block rear suspension. They ride every bit as good as last truck I used to run, a loaded air ride 2020 4900 Western Star. And no squeaks or rattles. Pretty impressed with the truck itself.

Now the M-Drive auto. They might be good on road, but not my thing off road on hills that are shown as 15% on the dash displays in our Cat rock trucks. Actually panicked me a few times because they feel like they go in to neutral between shifts there is such a long pause. And I spun out on one hill because it decided to shift (and pause) right at the peak of the hill. Yes I know I could have used manual mode, but wanted to see how they did in auto. I did not like at all.

But then I tried performance mode and performance plus and they performed a lot better. But in this application of big hills and having to slow constantly to almost a stop for giant potholes, they seem to get confused and shift way more than necessary. The MP8 505 has plenty of power to pull a gear but they would still shift down.

Not my cup of tea, I'll take a manual any day. But they might be nice for use in town or for idling along with a roto-mill.

Engine brake was pretty strong too, compared to Mack's of old.

Thx for the review😎

[cruiseliner64]

Thanks for the review.Iv never driven a road truck with auto gearbox.I have driven Volvo,Cat,Toro,Normet and Aveling Barford haul trucks with auto boxes and wouldnt be pushed on them.With haul trucks I'd say the problem is where are you going to get a clutch to take the power and shock loadings of 7/800 HP versus 150 tons or more....good pictures by the way.

Paul

[Mark T]

Those trucks might be better off with an automatic for the application they're in.   ( like Paul just said )

[Bullheaded]

19 minutes ago, Mark T said:

Those trucks might be better off with an automatic for the application they're in.   ( like Paul just said )

With some of the drivers they have had, yes, LOL

I think if I had to, I'd probably go Allison.