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6x6 Peterbilt Semi Truck

Tommy R

I wanna be Dave
Joined
Aug 19, 2008
Messages
4,273
Location
Austin, TX, USA
Hey y'all,

It's been a while since I've done a build. My Class Zero rig is still gathering dust. I picked up and built an SCX10.2, but I've been lazy mounting the Jeep body to it. So why not start a whole new project, right? :mrgreen:

I've always wanted to build a Tamiya semi truck. They're just so cool looking and I've been a fan of big rigs since I was a kid (maaaaany moons ago!). I've spent hours and hours watching those incredible expos in Europe where people build and drive their amazingly detailed trucks through scale cities, but sadly, it doesn't seem to be very popular here in the States. :cry: So that means if I were to build a semi truck, I would likely have to run it with my crawler buddies. Now make no mistake, converting one of these trucks to all wheel drive will absolutely NOT make it a crawler. However, I should be able to do mild trails with it and honestly, that's all I care about for this truck.

So which one to buy? The Euro cabover trucks like the Scania, Mercedes, and Volvo look fantastic, but all the front overhang and such a short wheelbase would combine to make an already ill-performing offroader nearly useless in our terrain. I would really need something with a slightly longer wheelbase and minimal front overhang. So I looked into the US trucks like the Globe Liner, King Hauler, Aeromax, Grand Hauler, etc. Some had a wheelbase that was just ludicrously long so they got ruled out. I also figured this truck would have a bit of a "heavy hauler" or "construction" type look so that ruled out the trucks with tall sleeper cabs. That left me with the Globe Liner and the King Hauler.

And after months of researching them and what it would take to make them all wheel drive, I opted for the King Hauler. The longer cab would likely give more options for drivetrain and the mandatory sound system! :mrgreen: Tower Hobbies hooked me up with a generous gift code and I already had a gift certificate so they got the order. Three days later....

BAM!
IMG_7249-XL.jpg


The first order of business is to do a stock 6x4 build with RWD only. It's crazy, but after being in the hobby since the '80s this will be my first Tamiya build! I can't believe they still use philips screws, but oh well. Once it's built I plan to convert it to a 6x6 and I'm still trying to decide which method I want to follow because there are plenty of options! I also figured I'll do some bodywork during this time. Since the King Hauler isn't really a Peterbilt or Kenworth or any other specific brand, I would like to put some effort into making it a Peterbilt. I'm not yet sure how far I plan to go with that, but it may include front fenders, a grill, and some badges. That would likely be all I'd consider, though there's certainly more options available to make it more accurate. Specifically, I'm after the look of a Peterbilt 359. Now let's build!!

Chassis all done!
IMG_7250-XL.jpg


For the axles I had something in mind. I didn't want to fully lock the axles because I'd like the truck to have a reasonable turning radius on concrete. However, it needs a true 6 wheel drive to get anywhere and open diffs just won't cut it. So I decided to try an experiment with some Gravity RC 2.5 million weight diff grease. My hope is that offroad it will lock up enough to spin all the tires, but allow diff action when turning on grippy concrete. Time will tell if it works! Here's the goop going in.
IMG_7257-XL.jpg


Roller status!! I also installed a Savox 1256 servo for the steering. It's only got about 277 ounces, but I think that might be fine for this type of rig.
IMG_7259-XL.jpg


Transmission coming together. I'll lock it into first gear for now, but eventually I'll have a servo to shift it.
IMG_7265-XL.jpg


Trans and an Integy 55t motor installed with the stock 10t pinion. I hear these things are way too fast with the stock gearing so I'll have to address that for sure.
IMG_7268-XL.jpg


Now the body and accessories. The base build is pretty much done. 8)
IMG_7278-XL.jpg
 
And Bamm she done..haha..
Looking forward to see how you make it a 6x6...was thinking of one of these toys in the future tamiya fan as i am and a 80's fan also..."thumbsup"
how many Hrs or days did it take for you to get it to looks as it sit right now..Can you tell me the WB looks big....
subscribe now...."thumbsup"
 
Check out that crazy articulation!! LOL
IMG_7279-XL.jpg


My plan all along has been to run a Tamiya TLT front axle in this thing. Same gear ratio as the semi rear axles and a good width. They're increasingly more difficult to locate these days, but I found one on ebay and guess what arrived from Canada over the weekend? :mrgreen: I gave it the same treatment as I did for the rear axles.
IMG_7301-XL.jpg


Then I greased up the gears, along with a coating on everything else in there to prevent rust since it may see some light water crossings.
IMG_7302-XL.jpg


And so much for an assembled truck! I yanked the front axle so I could figure out how I want to attach the TLT axle.
IMG_7304-XL.jpg


I am now at a crossroads. I need to determine how to mount the TLT to the leafs. The stock leaf spring has no holes in it. That would mean I'd need to drill two holes in order to attach it to the axle. Not sure how well this steel will drill since I suspect it may be spring steel? I also have Hi Lift springs, which has three holes in it. I may look into installing it, but am not sure if it will be stiff enough to support the weight of this truck. If anyone has thoughts or suggestions, I'm all ears!

Lastly, I still need to determine my transfer case choice, as well as my gear reduction method. But whatever I choose, it's looking more and more like I'll need to run the TLT upside down.....or maybe run my rear axles upside down if that's easy enough to do. Haven't looked into that yet, though. Again, any input is appreciated, but I've giving strong consideration to this transmission/transfer case:
1/14 rc car truck for tamiya 2 position 2wd/4WD Metal Transmission Planetary gear box
vjvjhv-600x600.jpg
 
And Bamm she done..haha..
Looking forward to see how you make it a 6x6...was thinking of one of these toys in the future tamiya fan as i am and a 80's fan also..."thumbsup"
how many Hrs or days did it take for you to get it to looks as it sit right now..Can you tell me the WB looks big....
subscribe now...."thumbsup"

I'd say it's got about a full day of building in it, but this was also the first time I've put together one of these Tamiya 3 speed transmissions so I took my time. Making the diffs a limited slip also added some time. The only bad part is the use of those stupid philips screws!! LOL

The wheelbase from front axle to rearmost axle is 450mm. So what's that, about 18"? Definitely not short! :mrgreen:
 
That's a great resource! If they had a hex head conversion kit for the Tamiya trucks, I'd have bought it in a heartbeat! I did replace some of the hardware as I was doing the build, but they use a shoulder screw in much of the suspension that couldn't be replaced with anything I had on hand.
IMG_7315-S.jpg
 
Been thinking about how to mount the TLT axle to this truck. The stock leaf springs are a multi-leaf arrangement with a rivet holding it all together and no through-holes. This would mean drilling through the stock springs in order to get them to attach to the TLT. Not ideal, but not problematic, either. Then I remembered I had some Hi Lift springs I'd bought years ago. They have three holes in them and the outer holes lined up perfectly with some of the holes on the TLT. Behold!
IMG_7308-XL.jpg


Note that I think I will run the axle upside down most likely. That will be required to get the drivetrain to all rotate the same direction. If need be, I think I could instead flip the rear axles. Looks like that would be easy enough, as well.

Before mounting it up, I measured the side-to-side spacing of the stock leaf springs is 74mm. The TLT's spacing is 79mm. So I'd need to space the leaf spring hangers and shackles out 2.5mm per side. I just used some 2mm spacers because that's what I had.

Front (hanger):
IMG_7312-XL.jpg


Rear (shackle):
IMG_7313-XL.jpg


And installed! I'm just using 6mm long screws (4 total), but the axle really feels secure. That could be sufficient, but I will likely drill all the way through it for a little more peace of mind.
IMG_7311-XL.jpg
 
Thanks, Justin! I'll be going with some Lesu all terrain tires all around with their aluminum wheels, as well. I'll run standard size in the rear, but will run the wider version up front for more grip/flotation.

Thanks for the links. I think the only one I had not yet bookmarked was the middle one. In fact, you should check your build thread on RCT&C. LOL
 
Well. That escalated quickly. Sold the stock wheels/tires and removed the body to do some work to it while I wait on the new wheel/tires to arrive.
IMG_7317-XL.jpg
 
your first tamiya kit? no way!? i love tamiya kits, they have some pretty cool/unique engineering in them at times. just ordered a tamiya kit myself today.

looking forward to this thing.
what tires you thinking?
 
Yep! In fact I've only owned two Tamiya cars my whole life. In the early '80s I had a Sand Scorcher and then in 2017 I bought a King Hauler. LOL! I'm glad I'm finally getting to build one. Really neat engineering involved, but I want to slap them for continuing with philips head hardware!

Anyway, onto wheels/tires. Here's what I'm getting. These are the rear Lesu tires:
LM-S1212S_1.jpg


Here's the wide fronts:
LM-S1212W_1.jpg


Rear wheels:
LM-W-2012.jpg


LM-W-2012_1.jpg


Front wheels: Gotta make sure to order the correct ones because standard fronts use bearings/bushings, not a 12mm hex drive like we're used to!
LM-W-2041-A.jpg


What it looks like installed. It's the closest I could get to the look I was after without spending an absolute fortune!
W-2042_2.jpg
 
i did something similiar, i bought two sets of rear alum dually wheels. then simply unbolted the outer wheel, leaving the inner wheel with the hex/pin drive to use on the front.
 
i did something similiar, i bought two sets of rear alum dually wheels. then simply unbolted the outer wheel, leaving the inner wheel with the hex/pin drive to use on the front.

Yep, that would work, as well! But for this build I wanted the extra grip and flotation of the wider front wheels/tires. I don't expect it to do "well" offroad, but I'd like it to have as much capability as it reasonably can while still being true to my vision of an "all conditions" hauler.

Kinda hoping some other folks in the area will get some semis (street or trail), but even if that doesn't happen, I'm really glad to have this thing. I've been wanting one for SO long and it's been a really fun build thus far. "thumbsup"
 
Looks awesome, can't wait to see where this goes, that 2.5 million diff lube is interesting too! Giving it a military/utilitarian 'bed' or?
 
Looks awesome, can't wait to see where this goes, that 2.5 million diff lube is interesting too! Giving it a military/utilitarian 'bed' or?

Thanks! Plan is to keep it with a 5th wheel. I'll eventually pick up a flatbed trailer for it and I plan to challenge it with hauling heavy loads of bricks and such across various terrain. I can also put drifters on it when we're have a drift event. :mrgreen: I'm going to make it like a nice looking, well cared for truck that isn't quite a "heavy hauler", but is designed to haul just about anything.....anywhere. Hence the driven front axle. I may also consider building a removable flatbed for it.

For the final product, imagine a mix/match of these trucks:
58650d556d778910f5122994.jpg


DSCN2017-S.jpg


AugClint1-M.jpg
 
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