Washboard Dirt Roads = Major Problems

[Loufish]

Saw a iTunes video of an Australian ranger raptor. Drag links and coils on the back

AND a Watts linkage....

 

[Supergumby5000]

Are there any drawbacks or trade offs associated with adding traction bars and Deaver/Icons?

I understand there is an associated cost.

The only drawback will be a lighter wallet.

I'de start with +1 (edit: over stock height) deavers and drop shackles before you get carried away with traction bars.

 

[Loufish]

Just to say...there are a lot of guys who go do washboard roads with their F250...try that some time and you'll find out how rough can be..(60-80 PSI)
Almost every truck/Jeep out their benefits from an off-road airdown, why you don't see it much is because many have no way of airing back up after their adventure...and don't forget how many Raptors/Jeeps are bought and are never going off road...

 

[Loufish]

I'de start with +1 deavers and drop shackles before you get carried away with traction bars.

I'm going to have to dis-agree....Going with +2 Deavers gets rid of the lift blocks....I went with +3 along with the extended shackle to give me stock height, knowing a switch to stock length shackles and instant 1" rear lift...

 

[Supergumby5000]

I'm going to have to dis-agree....Going with +2 Deavers gets rid of the lift blocks....I went with +3 along with the extended shackle to give me stock height, knowing a switch to stock length shackles and instant 1" rear lift...

when I said +1, my intention was 1 inch over stock. ridding of the lift blocks in lieu of shackles is definitely a reasonable choice though.

 

[jaz13]

Every spring and weight combination has a natural frequency, ie harmonic vibration. The most obvious example people are familiar with is a child pumping on a swing. Get the frequency wrong and you go nowhere. Get it right and you are flying 10' in the air.

The same applies to our suspension. Washboards are created by a vehicle suspension's natural frequency. If you stopped and measured the gap between the peaks of all the washboards on a stretch of road, you would be amazed by how precise the distance between every ridge is across the entire stretch of road.

The reason you don't feel the washboards as bad in your 4runner is those washboards were created by pickup trucks. Think of your 4runner as the kid pumping at the wrong time and is why his swing isn't going anywhere. If 4runners were the only vehicle that drove on a stretch of road, the washboards would form around the natural frequency of the 4runner's suspension and it would feel just as bad as your Raptor does now. And conversely, your Raptor would cruise effortlessly through that section that was killing the 4runner. Pickup trucks are far more common than 4runnners and Jeeps and is why washboards affect trucks a lot more than other vehicles. (trucks made the washboards)

As for the reason why it feels like you have no control of the truck in those washboard sections is because the tire is skipping from washboard to washboard and is spending more time in the air than it is on the ground. It feels like the truck is floating because it actually is floating.

As other people have pointed out, airing down is one way to change the way the wheel/tire/suspension react to the bumps. So rather than move the suspension arm, the low-pressure tire absorbs the bumps and never gets a chance to excite the suspension.

Anyway, there is nothing wrong with your truck. This is just physics.

 

[BushwiickBill]

Airing down for proper offload usage is mandatory but you don't have to go to the extreme with it either. I just finished a desert run (77 miles) all dirt today running 38F, 34 rear with some heavy washboards with no issue of control in my 19. I would air down more for offloading but that pressure works great for street and offload and I'm lazy because I don't have a Power Tank or Viair. I feel some of it is the driver...can't be afraid to push these trucks. High speed is what they love!

I'm wondering if there is a valid issue with the original poster's truck if it's as extreme as he states? He's comparing it to an old 4-Runner which performed better in his opinion than his Raptor on the same terrain. Just that statement means there has to be an issue with truck, driver (not sure of experience) or both.

 

[Loufish]

when I said +1, my intention was 1 inch over stock. ridding of the lift blocks in lieu of shackles is definitely a reasonable choice though.

Ahh......make perfect sense now...

 

[zombiekiller]

The only drawback will be a lighter wallet.

I'de start with +1 (edit: over stock height) deavers and drop shackles before you get carried away with traction bars.

i really really wish folks would STOP giving out mod advice when they havent used said recommendations themselves, and ESPECIALLY when they dont understand what works together and what doesnt.

/PSA ON

TRACTION BARS ARE NOT COMPATIBLE WITH DROP SHACKLES.

Drop shackles also can and WILL lead to accelerated leaf spring wear if you offroad a fair amount. Drop shackles also can contribute to some degree of axle wrap due to the articulation movement that they add.

If you use drop shackles with traction bars, you will create bind on downtravel. You will rob 4 or 5 INCHES of downtravel from the truck if you install traction bars and drop shackles.

DO NOT USE THESE TWO PARTS TOGETHER.


/PSA Off

 

[Yoshi]

If your tires are not keeping contact with imperfections in the road surface, the Fox factory rebound is set too slow. Airing down will be your band-aid unless you can tune the Fox factory shocks for faster rebound.