Newbie - Mack Trucks

[AATA]

This is my first post, so first I’ll start by thanking everyone for all the great information. What a great site with an endless amount of information and some very knowledgeable members. I also spend a lot of hours staying up at night designing my dream vehicle in my head. I'm sure others can relate!

With that, my dream vehicle is something like this, but home built (with the help of a friend / local yatch builder.

http://www.unicatamericas.com/photos_ex70.html

I don’t have the time or money right now, but someday I will, so I’ve spent many hours reading this forum, designing the electrical system, plumbing system, drawings on google sketch, making lists and researching anything I can related to this type of vehicle. I would like to build something larger than the FUSO (possibly the FK260-FK330 will work), but for my use, I would rather have a larger vehicle and sacrifice some maneuverability. The vehicle will be used to replace an enclosed trailer and 4x4 truck set up that we take to our local desert and also for adventures across North America. We could probably go without 4x4 or 6x6 except we like to camp in a remote area in the local sand dunes and would like to do the same on any other trips. Once I’m more serious about the build, I will post my plans and would appreciate any feedback.


With that said and what actually motivated me to post for the first time is this….

http://www.mackterrapro.com/

I’ve been reading about different options for cabover trucks and wondered if anyone has considered these for a build platform or the earlier MR688. Obviously a lot heavier duty and possibly too heavy, but for something as large as the Unicat above, this chassis seems like it would work great. They offer a stock suspension system called the M ride, which from what I’ve read is similar if not exactly the same as the T Ride from Volvo in other countries. (Mack is owned by Volvo, so this would make sense). The site says the M Ride provides 17” of suspension articulation which seems like a lot to me for this type of truck. Would be curious what the Unicats are? It also seems like parts would be readily available in different countries based on the information on the website. I mainly plan to travel in North America, so this isn’t a main concern now, but I would like the option in case I make it to other countries in the future (I don’t want to build 2 of these in my lifetime). I would be curious if any of the members outside the US are familiar with these trucks? I believe they only come in 4x6, but I talked to a place in Oklahoma that said they can convert it to 6x6. I would be curious if anyone on this site has converted a medium to heavy duty truck with good success. Based on my brief conversation, it sounds like they use common factory components that are used on other 4x4 and 6x6 factory built trucks, so the parts are proven.

While researching the M ride, I also found some suspension systems that could be used on a wide range of vehicles. I haven’t seen these mentioned, so sorry if this is repetitive. Anyone have any experience with any of these?

http://www.hendrickson-intl.com
http://www.ridewellcorp.com
http://www.raydanmfg.com

Overall it would take some custom work, but seems like it could be a very good platform. Any thoughts would be appreciated?

Sincerely,
Trevor

 

[charlieaarons]

Some of the criteria for easy convertibility to AWD are:
availability of rear axle suitable for SRW
availability of rear axle locking diff
availability of appropriate transmission for driver's skills
Also, issue of 2007/2010 emissions with heavy EGR and SCR/DPF, vs. getting a "glider kit" from a pre2007 chassis so that a pre 2007 engine can be used that is compatible with higher sulfur diesel.

Charlie

 

[AATA]

Some of the criteria for easy convertibility to AWD are:
availability of rear axle suitable for SRW
availability of rear axle locking diff
availability of appropriate transmission for driver's skills
Also, issue of 2007/2010 emissions with heavy EGR and SCR/DPF, vs. getting a "glider kit" from a pre2007 chassis so that a pre 2007 engine can be used that is compatible with higher sulfur diesel.

Charlie

Charlie - thanks.

Can you elaborate or do you happen know any specifics to this truck.

Is there a reason the above aren't possible or wouldn't be cost effective. It may not have the same off road capabilities as your unimog but with a locker and the right axles do you see why it wouldn't work and work good.

I've been racing cars for 15 years and although this would by no means be a race car is there a reason I wouldn't be able to drive it. I can't imagine they're too difficult.

The mr688 pre 2007 was almost the same thing.

Thanks.

 

[AATA]

Anybody? Is this unchartered territory or is there a special hand shake to be part of the club? :sombrero:

 

[lowenbrau]

Anybody? Is this unchartered territory or is there a special hand shake to be part of the club? :sombrero:

I'm pretty sure Charlie gave you a homework assignment. (he does that)

Can your garbage truck address the concerns listed?

It is an interesting proposal. I've seen a lot of that style of Mack for sale used for very reasonable prices and have wondered about its feasibility as a tow rig.

The trouble to some with a Mack is that it uses a Mack engine. Some guys don't like them and I'm not sure what the ramifications are for getting worldwide parts and service support.

 

[AATA]

I'm pretty sure Charlie gave you a homework assignment. (he does that)

Can your garbage truck address the concerns listed?

It is an interesting proposal. I've seen a lot of that style of Mack for sale used for very reasonable prices and have wondered about its feasibility as a tow rig.

The trouble to some with a Mack is that it uses a Mack engine. Some guys don't like them and I'm not sure what the ramifications are for getting worldwide parts and service support.

Thanks for the response. I have addressed them below based on what I understand and learned from calling around to shops that convert vehicles like this.

availability of rear axle suitable for SRW - There's a wide range of axles that would be more than adequate for this unless I'm missing something? There's already a wide range of heavy trucks converted for mining, rescue, etc.
availability of rear axle locking diff - I was told thereare lockers readily available as long as the axle is 12,000 lbs and above. From reading the Medium/FUSO truck forum, this sounds somewhat accurate?

availability of appropriate transmission for driver's skills -
Not sure I understand why this is an issue, but I'm sure I can manage.

Also, issue of 2007/2010 emissions with heavy EGR and SCR/DPF, vs. getting a "glider kit" from a pre2007 chassis so that a pre 2007 engine can be used that is compatible with higher sulfur diesel. - I addressed this in my first post. The MR688 is the earlier model without all the low sulfer gadgets. I just sent the terrapro site because it's fancy and they are practically the same thing. I would buy an older one, which as you mentioned can be found very reasonbale with low miles.

I too question how available the parts and service are. I would probably travel North America before I travel anywhere else, but it is something to consider down the road. With that, here's a quote from their site that makes it sound like they are in a wide range of countries. Being part of Volvo might help a little too? Maybe some of the members from around the world can add their input on these in other countries.

"Founded in 1900, Mack Trucks, Inc. is one of North America's largest producers of heavy-duty trucks. MACK® trucks are sold and serviced in more than 45 countries through a worldwide network of more than 670 sales, parts and service centers."

 

[charlieaarons]

availability of appropriate transmission for driver's skills -
Not sure I understand why this is an issue, but I'm sure I can manage.

3choices:
Traditional nonsynchro multispeed (8-18 spd) manual
autoshifting manual
automatic

This is a very important decision point in big truck purchasing.
I'm sure a true Allison auto is available since it is used a lot in urban apps.
My personal favorite is the Roadranger 9LL which is an 11 spd manual with super low 26:1 low-low. Now available in autoshifting configuration. I don't if you can even get Roadrangers with Macks, what do they come with?

Some drivers don't do well with non synchro manual transmissions.


Charlie

 

[AATA]

3choices:
Traditional nonsynchro multispeed (8-18 spd) manual
autoshifting manual
automatic

This is a very important decision point in big truck purchasing.
I'm sure a true Allison auto is available since it is used a lot in urban apps.
My personal favorite is the Roadranger 9LL which is an 11 spd manual with super low 26:1 low-low. Now available in autoshifting configuration. I don't if you can even get Roadrangers with Macks, what do they come with?

Some drivers don't do well with non synchro manual transmissions.


Charlie

I completely agree about the non-syncro. I would never want one for an expedition vehicle. I drove the race transporter, which is 18 speeds (just around the block). Not really difficult but it would be a hassle. Especially in traffci!

It looks like there's an option for the Roadranger 8LL rather than the 9LL. It looks like the main difference is the 9LL is a high reduction trans. The 8LL is a 8+2, so paired with a 2 speed transfer case, this would probably be a great option. What do most prefer between an automatic transmission and a manual transmission like the Roadranger? Below are all the transmission options for the Mack. The Allison 4500 isn't a bad option either if autpomatic is preferred.

TRANSMISSIONS
MODEL SPEEDS RATIOS (LOW/HIGH)

Mack
TM308 8 17.77/0.71
TM308M 8 17.77/0.71
TM309 9 25.21/0.71
TM309M 9 25.21/0.71
T309 9 11.40/0.71
T309(LR) 9 13.93/0.71
T310ME 10 17.35/0.73

ALLISON
4500 RDS 5 4.70/0.76
4500 RDS 6 4.70/0.67

ALLISON—FOR FIRE PUMPER SERVICE
4000 EVS 5 3.51/0.74
4500 EVS 5 4.70/0.67

EATON FULLER
RTO-14908LL 10 14.56/0.74

Thank you!

 

[AYIAPhoto]

Some drivers don't do well with non synchro manual transmissions.

I drive these things every day(non syncro transmission heavy trucks). Once the tires hit slightly soft dirt or sand, shifting at low speeds becomes a major hassle. Double clutching or any other "gentle" method goes right out he window once the truck quickly starts to lose momentum. Those trannies are made for street driving plain and simple. From the second I hit the workface of a landfill or a sand pit, even just a dirt lot being excavated, the trans generally stays in 1st gear(sometimes low or low/low).
Look for an auto-shift or true auto(auto-shift will get better mileage but you sometimes forget there is a clutch and stall when first getting used to it).

 

[AATA]

I drive these things every day(non syncro transmission heavy trucks). Once the tires hit slightly soft dirt or sand, shifting at low speeds becomes a major hassle. Double clutching or any other "gentle" method goes right out he window once the truck quickly starts to lose momentum. Those trannies are made for street driving plain and simple. From the second I hit the workface of a landfill or a sand pit, even just a dirt lot being excavated, the trans generally stays in 1st gear(sometimes low or low/low).
Look for an auto-shift or true auto(auto-shift will get better mileage but you sometimes forget there is a clutch and stall when first getting used to it).

Thanks for the real world knowledge. Can you please provide some insight as to other experiences with this truck like cab noise and reliability? I'm not sure what year you've driven but they made a statement for the new model about reducing noise, so I was curious if the older models are really loud.

By chance have you driven an automatic version?
Thank you!

 

[charlieaarons]

TRANSMISSIONS
MODEL SPEEDS RATIOS (LOW/HIGH)

Mack
TM308 8 17.77/0.71
TM308M 8 17.77/0.71
TM309 9 25.21/0.71
TM309M 9 25.21/0.71
T309 9 11.40/0.71
T309(LR) 9 13.93/0.71
T310ME 10 17.35/0.73

ALLISON
4500 RDS 5 4.70/0.76
4500 RDS 6 4.70/0.67

ALLISON—FOR FIRE PUMPER SERVICE
4000 EVS 5 3.51/0.74
4500 EVS 5 4.70/0.67

EATON FULLER
RTO-14908LL 10 14.56/0.74

Thank you!

I like that TM309!!
25.71 to 0.71, that's as good as a 9LL
Just in 9 spds? It's got about 57% ratio splits.
http://www.macktrucks.com/assets/Specs/tm3091361323.pdf

Charlie

 

[AYIAPhoto]

Can you please provide some insight as to other experiences with this truck like cab noise and reliability?

I was speaking of non-syncro transmissions. I have not driven that particular model of Mack, but those I have driven tend to have quite noisy/rattlely interiors.
Macks tend to be referred to as "Owners" trucks. They generally take a beating and hold up, but are not much in the comfort department.

I'm not sure what year you've driven but they made a statement for the new model about reducing noise, so I was curious if the older models are really loud.

A lot of the new truck are much quieter than the diesels of years past. I know someone who picked up a WesternStar with the new "clean Idle" Detroit in it. It really isn't much louder than my ZJ at idle. As far as in cab noise goes, that depends on how they are fitted out. Over the road trucks have much more sound deadening in them, while those designed to be used as utility/dump/garbage trucks are much more stripped down.

By chance have you driven an automatic version?

The last large auto I drove was an International DT466/AT545 combo while working as a mechanic for a school bus company. I wasn't really that impressed. I did however lose an impromtu drag race to a buddies Kenworth with an Auto-shift. You simply can't row 8 gears as fast with a non sincro trans as the 18speed auto-shift can go through its gears.

 

[dzzz]

In the real world the Mac linked is too heavy. For a larger expedition camper a chassis weight of 9K-15K is about right. The ideal beefier cab chassis would probably be about 10-12K lb with a 8-10K payload. The heavier cab/chassis we use now are about 15Klb. That's probably unnecessarily robust for an expo vehicle.

Ford/GMC medium duty trucks are lighter and have a history of 4wd conversion. I've never been in an American medium duty truck that is nice to drive. I'm sure that air seats and sound insulation improve the situation.

anything less than 8 speeds and syncro would seem like trouble in a heavier 4wd vehicle.

 

[AATA]

In the real world the Mac linked is too heavy. For a larger expedition camper a chassis weight of 9K-15K is about right. The ideal beefier cab chassis would probably be about 10-12K lb with a 8-10K payload. The heavier cab/chassis we use now are about 15Klb. That's probably unnecessarily robust for an expo vehicle.

Ford/GMC medium duty trucks are lighter and have a history of 4wd conversion. I've never been in an American medium duty truck that is nice to drive. I'm sure that air seats and sound insulation improve the situation.

anything less than 8 speeds and syncro would seem like trouble in a heavier 4wd vehicle.

At first I thought it might be too heavy too, and maybe it is, but the MAN trucks used in the Unicats aren't any lighter.

It looks like the weight for this truck http://www.unicat.net/en/info/MD83h-MANTGS6x6.html is 39,660lbs fully built and based on some of the videos of this thing, it can hold its own off-road. If I'm looking at the right weight on the MAN site, I believe the weight of the truck without the conversion is around 26,000 lbs for 6x4 TGS? Something this big will obvioulsy never be like off-roading in a Rover, but I'm not sure the weight is the main issue. I would be more concerned that it's too big overall and would be difficult to drive through small towns, windy roads, etc.

I would assume the tatra, Man Kats, OshKosh, etc. aren't much lighter, but this is just speculation?

Simple solution would be if MAN started selling trucks in the states!

 

[dzzz]

Much over 28' the angles become difficult. You wouldn't have a 40K lb truck at 28'.
Few 6x6 expo campers have been built. There's a reason the photos come from the desert. When you start to look at he actual math of an offroad capable line-in camper few people conclude that a 35' 40K lb vehicle is the way to go.
For 2 people I think about a 17-18' cabin is about the "sweet spot". 16' works but is a bit short on stoarge in a unicat design. Many people have certainly done fine with less.
The toater home thing is great too. But no one ships those vehicles to other continents or drives off road.