Forum boards for students, parents, teachers, travelers, gamers. Search message boards, post classifieds/ ads, give tips, share ideas, reviews/ discussions, ask questions, find information topics, free jobs forums, free blogs on games, kids' classes, music, education programs, schools, colleges, work visa
Forums Job Forum Jobs Schools Online Edu Kids Area Games Visas
Post without signing-up (optional).
Post a message or Search Forums
Author Message
Dustin Dustin, Posted: 2009-01-03 17:41:01
I'm about to start building my mud truck that would be capable and could compete with anyone in the mudhole. I aim to have 41 inch tractor tires and have a total weight under 2.5 tons. I am not sure what suspension to run, coilovers with a fourlink setup front and rear or leafsprings.I would appreciate any suggestions on gearing, suspensions, or drivetrain.

Pictures, drawings and advice appreciated.
Neil Neil, Posted: 2009-01-05 12:56:42

I think you will have to review your budget and extent to which you are ready to go. How committed are you? As yourself a question - Do you need a capable mud truck for sports or just a show off car?

If you are going for 41'' tires - you should loose everything your car has in excess - massive interior and exterior body. Scrap your truck body and leave just a frame, engine and axles. That is all you need from your truck. The rest should go to scrap yard. Cutting is easy:

4x4 4x4, Posted: 2009-01-17 08:24:08

Start from the basics - make the frame as small as possible and as light as possible. Cut off all unnecessary parts and shorten it as need.

Weld the frame well and make sure it won't flex too easy. It must be very strong at the ends.

Now put your engine as low as you can to keep the mass center low and move engine to the center of the car.

You may have problems with moving the engine towards the center of the frame because your wheelbase is very short and the transfer box is too close to the rear axle. For that reason we have to shorten the transfer box. Original NP208 C2 transfer boxes are long enough:

And we need those extra 3,5 inches. The final result is 3,5 inches shorter transfer box :

We can start making the body now. It must be durable to withstand rollovers and still be light. We are going to use pipes to make the frame, fiberglass and aluminum to cover everything:

Fiberglass will be made out of 5-10 layers depending on the strength we need in particular place:

Extreme4x4 Extreme4x4, Posted: 2009-02-14 03:04:10

Fullsize truck's are the mud champions because they have the heavy-duty hardware required to go through it without breaking parts. But that is true only if we are speaking about regular 4x4 cars. Some wheelers feel long-wheelbase rigs are better for stability, others believe short-wheelbase rigs are just as capable. Short wheel base is better for mud, long wheelbase for hills and rock crawling but it still depends on every situation. In general, we think the strongest building platform for a mud truck is a 3/4- ton truck. Even though these trucks are a little more expensive initially, having the heavy-duty components from the start will save you more money than if you buy a 1/2-ton and upgrade it. Built big-blocks are required on mud trucks because of the torqe v-8s produce. A mudders engine needs plenty of low end grunt, so make modifications that will increase the power output at a low rpm. If you have a small-block, there are plenty of aftermarket parts that increase power, and these engines are cheaper to build in most cases. Regardless of your engine type, all that torque needs bulletproof drivetrain components to channel the power to the ground.

Dana 60s or Dana 44 and NP205 or NP208 transfer cases are prevalent in mud trucks. Mud is hard on drivetrain components because it's either sticky and requires lots of power to keep the tires turning.

Straight-axle trucks are commonly used because their assemblies are usually stronger and easier to modify than independent suspension assemblies. Portal type axles are the best of the two worlds - strong assembly and you don't have to plow the ground that much.

Axle articulation isn't as much of a concern on a mud truck as it is on a trail rig. A stiff suspension works well in mud because it reduces axle warp and wheel hop. Axle warp can hurt drivetrain components and a wheel hop reduces traction. Since traction is the name of the game, a dedicated mud truck should have heavy duty spring.

Lockers for the front and rear are essential.
4x4 4x4, Posted: 2009-02-16 13:00:22

Next update on truck remake:

There were loads of tiny cut & weld & redo but we have moved a bit forward. That has brought a better shape of the new truck and can give you a better idea of what is going to be there and what's not.

The outer part, sides and the bottom was made out of 1 and 2 mm aluminum. We found out later that although we can save 50% of the weight by using 1 mm aluminum - we have loads of problems with it. First of all - it does not keep the shape well unless you have it shaped/bent. And the second and the most important - it's impossible to weld it fast no matter which method you are going to use - it is going to be either slow or you make a hole in it. It is easy to work with 2 mm aluminum - it is strong enough for every purpose. It is not recommended to use "hard" aluminum - you cannot bend it more than 70 degrees - it will break if you bend it more. Don't use "soft" one either. Use "semi hard". it is stiff enough, yet allows you to bend it 130 degrees no problem. You can see the result in the image below:

When it comes to gas/diesel tank - you MUST use 3 or 4 mm aluminum. That gives you enough strength to withstand the rocks, tree branches and anything else and it won't changes it's shape when you weld it using MIG. 4 mm aluminum tank with 130 L capacity will weight 33 pounds (15 Kg) and is light enough for that size and strength.

4x4 4x4, Posted: 2009-02-27 15:00:15

Once you have finished with the welding and cutting, have made all the body and frame parts and connections - proceed to the next step - painting and corrosion cover. f you have a chance to make powder painting go for it (it's more expensive but lasts much longer) otherwise any metal paint will do.

To do the job right disassemble everything you can and paint everything separately - only then put it back together - engine and the axles come in first, then put the brake system wiring, oil and water cooling pipes.
john dye john dye, Posted: 2009-03-04 19:13:35

im looking for axils for my newest mud rig can you help me
4x4 4x4, Posted: 2009-03-08 13:39:31

What type of axles are you looking for? What tyres are you going to mount and what is the car weight?

Also - another update on truck :

Body has been painted, all parts assembled and ready to be used. Doors, front of the car is in the assembly progress:

The rear of the car is ready for the radiator, battery and fuel tank mount:

Anon. Anon., Posted: 2009-03-26 02:36:05

A few weeks may take to complete all the minor tweaks and to install the wiring. Although such car has a very minimal wiring - it still needs the usual stuff - headlights, turn lights, rear lights, wipers and the dashboard. You don't really need the heater or cooler (you can open your window to get some fresh air). But you do need to see the temperature and the pressure in your engine and probably RPMs as well as your battery voltage. The dashboard:

So that still leaves you with some 10-15 fused wires. Make sure you have enough cooling power in case you are stuck in mud for 30 minutes and you have to rev at 3000-4000 RPMs for a while. It may blow your engine if you don't have enough cooling.

Anon. Anon., Posted: 2009-04-10 14:26:25

The truck is somewhat finished and the test run will begin now to find any weak points on it. The length and the width of the car is the same as a two door Daihatsu Rocky ( a bit smaller than Jeep Wrangler).

Facts sheet:

- took exactly 4 months to build by 4 guys
- an estimate cost - 50,000 $ USD
- Fully loaded with 130 L diesel fuel tank weights 2120 Kg ( 2 tons when empty). - 6.2 L V8 diesel 155 bhp engine
- 3 gear automatic gearbox
- fully locking both axle differentials with 7.1:1 transfer - top speed 100 km/h
- 12,000 LBS pull electrical winch in front and rear - can operate while submerged in water up to 2 m (6.6 ft) for 2 hrs
- approach angle front/rear - 100 degrees
- ground clearance - 48 cm (19 inch)
- driver/passenger seats with 6 point harness - steering is fully hydraulic (no mechanical link from steering wheel to wheels)

Some photos:

Radiators, sand tracks, X-jack and an axe in the rear:

Car parts used:

- Volvo C304 Axles with C306 differentials to get lower transfer ratio
- UK Audi A4 windscreen wipers and motor to save space
- Chevrolet Blazer engine from M1009 with two generators (converted to 12 V from military 24 V system)
- Mercedes Unimog 404 rims to fit 41'' tyres
- hydraulic steering from sand racing car
- Audi 100 door mechanisms
- Nissan Patrol (2 door Spanish version) frame shortened by 1 m (3 ft)
- Volvo C303 shock absorbers
- Mazda 121 braking system booster
- Volkswagen Passat B5 brake pads & caliper to allow having disk brakes on Volvo C304 axles (instead of drum brakes)
- some minor parts from BMW 320 to protect hydraulic steering and cardan-joints

and loads of aluminum to make the car lighter
Anon. Anon., Posted: 2010-01-03 13:11:05

Some project updates after 8 months:

Alloy rims fitted instead of standard which made each rim 13 Kg lighter saving a total of 52 Kg. It made a huge improvement in acceleration, the car is climbing much better and goes through mud easier. BMW 20" x10.5" alloy rims were used with center part replaced to have 8 bolt fitting.

The tread of the tires was shaved down to have only 2-3 cm deep tread which made 5 Kg off each tire making everything even easier on engine and transmission. This has put the end to breaking shafts and gears in the axles when accelerating through stumps and rocks when they are well hidden under the mud.

The grip of the tires went down a little but not very noticeable but since the car got lighter - i can have a higher gear most of the time which gives the muscle to move forward in the deep mud.

Electrical winches (rear and front) were replaced by 1 hydraulic industrial Ramsey winch 8000 lbs. It can pull me forward and backwards as needed.

This has lead to Howe Performance supplied power steering pump replacement to a more powerful hydraulic pump making 60-70 L/min which is just enough for the Ramsey winch. V - belt was replaced by a high quality chain and no more lost steering after deep water when V belt just goes off after an hour of wet driving.

Since the pump is more powerful - I can turn the steering wheel much faster as well - TC pump from Howe Performance wasn't enough at all.

You can see the pump on the chain, the hydraulic oil tank and filter in the pictures below:

To be able to use one winch for forward and backwards pulling - Ramsey winch had to be installed in the rear of the car and a stainless steel pipe was run to the front for the winch cable (so i can pull forward).

Since electrical winches are gone and I don't need much of the electrical power - one alternator was removed (as one 100 A alternator is enough now).

The speed of the Ramsey winch is 40 RPM which gives 12-22 m/min pulling speed (depending on which layer you are running as the more cable you have on the reel - the faster it pulls)

Now the total weight of hydraulic winch with all the pipes, oil and other stuff - is equal to 2 electrical winches. But the pulling speed is 6-10 times greater which means a 22 m long mud hole can be done in 1 min compared to 10 minutes with electrical winches. How about 10 mud holes of 22 m? Hydraulic winch - 10 minutes, electrical - 2 hours if the engine and relays don't get too hot and don't burn (which will happen most likely at the end if there isn't enough time for them to cool down). In reality - you will need 4 hours with electrical winches as you must cool them down for 15-20 min after 10 min constant use under load. And - your batteries will most likely be flat all the time while alternators going crazy at the same time.

Offload race with electrical winches is a no go. Tested and lesson learnt. If hydraulic winch is installed correctly - you will forget it (just grease it from time to time) and just keep on (ab)using it.
Anon. Anon., Posted: 2010-06-03 14:24:02

dude your work is awesome you should make a magazine about this stuff it would be genuine and would be a real hit in the redneck world
Anon. Anon., Posted: 2010-08-07 08:50:21

The TR3 offroad truck is for sale, interested parties should leave a message with their offer. The car is in excellent shape, with almost all bearings, seals replaced by a brand new. Additional pictures can be posted here or a test drive can be recorder in a desired place (mud, swamp, hills,woods). Many spare parts and technical support tools can be added for extra. There are 4 medium size tool boxes with every part and tool you might need.


Even such a road is a good road for it:

82Kchevy 82Kchevy, Posted: 2011-07-27 19:33:49

i am just trying to build a fun truck, but i have no idea what im doing. its an 82 k10, and i want to build a could be daily driver, but aint afraid to get in the mud. i have ideas and mechanical incline. what i dont have is the experiance with what kind of rear\front ratio's. torque\horsepower, and most of all suspension. can you help?
Blazer Blazer, Posted: 2011-07-28 15:03:12

Good question, but it can only be answered once you decide on the tire size. What size are you going to put on? The width and size. It also depend on a thread. Put a picture of the tire and dimensions for better assistance.
79 K-10 454 79 K-10 454, Posted: 2011-09-20 21:12:56

Question? Im building a 79 K-10 4x4. The plan is to have 4 wheel hydraulic steering. What front end should be used the accomplish the rear steering portion of this build? Im hearing a dyana 60, but I also need one that is centered so that my pinion angles will not be thrown off so dramastically. Ive turned wrenches my whole life and this is pretty much all that is slowing me down so far. Im trying to get around haveing to get new axle tubes and custom cut shafts. Please help me with ideas to make my 4 wheel steering monster a reality!
Austin Austin, Posted: 2011-11-23 12:24:50

Blazer Blazer, Posted: 2011-11-23 12:50:13

79 K-10 454 - yes, DANA 60 is a good choice and probably one of the better ones as most other axles will definitely break at some stage. Installing new axle tubes and new shafts would be one of the easiest ways to get around.

However - you could try turning transfer box case one or the other side. It can be turned around either way and this would allow you adjusting the angle for you.

Alternatively - you could install a 1:1 transfer case right on the rear end axle pinion to shift it 4-5 inches. PTO on the gear boxes work the same way.

By doing so - you not only get pinion shifted to the center, but you could have it even lifted up. That way you get better pinion angle vertically and horizontally. Something similar to this (just smaller one)

to 79 K-10 454 to 79 K-10 454, Posted: 2012-02-09 16:00:09

If you can do it, go for independant suspention.
Jonathan Jonathan, Posted: 2012-12-14 12:27:35

Dustin, My name is Jonathan and i am a mud bogger myself. I build my own trucks along with race cars. The best products you should go with is Sky Jacker from You should go with the leaf springs the will support your truck more and they are not easy to break. I hope this helps you and you build the best truck that you can. you can look at my trucks on facebook by looking up Apollo Frye. I was in the 4 Wheel magazine at one time. Good luck to you and if you have any questions about anything else just hit me up on face book...
Dustin Dustin, Posted: 2012-12-22 14:43:00

Hello Jonathan,

But leaf springs are not giving the flexibility you can get with coil springs. Thus less articulation. Correct?

Could not find your trucks page. Could you post some photos here?
gabriel gabriel, Posted: 2013-03-14 14:26:15

hey wat u need is a good springs dat in just in case dat your truck does not brake down u need to get rally spring hit me up at 489-4968 gabriel subia
gabriel gabriel, Posted: 2013-03-14 14:51:49

go to the mud bogs inc in belen nm
Big_Wood Big_Wood, Posted: 2014-02-01 21:06:47

I run coil-overs on 5 ton with 72" Racing Kanes on a alcohol injected 632 big block Chevy. However it is a Chevy 1500 crew cab Std bed if that makes a difference.

To Post Replies or New Topics, you do not have to be registered. However, if you wish to receive an email alert when a new entry is posted on this topic, you will first have to Sign-Up and confirm your registration. 

Write your Reply to this Topic below: *
Only genuine replies and messages are permitted. If an entry is of low quality, or not related to the topic, or is deemed not genuine, it will be deleted. For privacy and anti-spam purposes, it is not advised to enter an email address or phone number into forum messages. Simply ask the topic readers to leave a message here (Registered users have the option of receiving an email notification each time a reply is posted on their relevant topic).

Non-Registered users should leave the password field below empty. Your Username entry (to be associated with your post) is compulsory, and should be between 2 & 17 characters in length.

Username: *