mrtremere

I have 2.5 Terraflex Lift and Suspension with Rancho x9000 Adjustable shocks. Tires are Nitto Terra Grappler 35".
We went to the Mud Caves in Anza Borrego. On the way in I lowered my air and the ride was still pretty rough.

On the way back My sisters X5 blew through it on street tires. I ended up having to readjust my steering wheel at the end of the trip is was soo off.

I recap:
Did I need to air down more?
Adjust my Rancho shocks or replace them with something more heavy duty?
Get lighter tires / These are E-rated side walls.
Or slow the fcuk down and accept my Sisters glorified station wagon is better desert runner.

grumpy1

not sure what your air pressure was but if you weren't under about 18 psi its going to still be a rough ride. I also haven't had very good luck with the Rancho shocks that I have had, always had a rough ride. I did see an episode of Mythbusters where they were driving on a washboard road and the faster they went the smoother the ride was so maybe you weren't going fast enough.

mkjeep

You should air down to 10-12psi with those tires and disco the swaybar.

mrtremere

Yea i was about 15 psi and disconnected.

mkjeep

Weird, must be the shocks and the setting. I have Toyos, 4in TF, and Elka shocks. Couple years ago in Moab Joe from TF and me were running 60-70mph in washboard sections. Walked off and left everyone.
I think the guy in the TJ with the RE longarm and Camp Crocker in his monster jk on 40's slowed some of the others down though.

mkjeep

Try 10-12, it does make a difference from 15. I don't know what u should set the ranchos on though. Maybe someone who runs them will chime in.

armedtotheteeth

Try Fox Shox.

RWJ

I added king adjustable shocks and they are amazing on washboard even at 25 pounds of tire pressure. X. My brother put kings on as well and as he said they are worth the money. They perform amazingly. Good luck.

Runewolf1973

This actually seems to work...for me anyways. Even at 30 psi on my Toyo MT's, if I keep a decent enough speed on a gravel road, it lessens the bumpiness of the ride. It's like the tires sort of "float" over the washboard whereas when you go too slow the tires have more time to dip into every little rut.

JPop

This pretty much has to do with shock valving. Washboard type roads at speed want a very low rate for compression and a high rate for rebound. Not exactly sure how those Ranchos are valved, but if the adjustability leaves the rebound/compression rate the same, they will probably beat the hell out of you on that type of terrain.

The shocks on my truck often used at speed and washboard type surfaces have a one way check valve, providing little to no compression on the upstroke and 100% damping when rebounding. What this does on washboard type surfaces at speed is actually drops the ride height and keeps the vehicle solidly planted. The springs do the work on compression and the shocks do the work on rebound. What you don't want in this situation is the shock acting like a spring on compression.

If this is something you do frequently, you might want to look to someone that does custom shock valving. Also keep in mind that with tire inflation rates no matter how much air you let out, they will always have a 50/50 compression/rebound rate. While lowering the pressure will soften the ride, it will also introduce some bounce which is not where you want to head for driving at speed on washboards.