Need Help - Truck Shocks

[CastAndBlast]

Alright ladies and gents, quick question that has me stumped...

Truck - 2010 Ford F150 King Ranch 4x4, Leveling kit 2.5" front/ 1" back

A few weeks ago I blew out the top bushing on one of my rear shocks. I noticed a knocking sound coming from the rear right tire. Upon further inspection, the bushing was crushed and the shock mount was knocking every time I hit a bump. While I was at the auto parts store getting wiper blades, I asked if they had shocks for my truck. Sure enough, they had 2 Rancho 8000 or 9000 ( I can't remember). So I go home and swap them out.

Everything is great now, no knocking sound. However, now when I hit any small bump it feels like I am going over a washboard. The only thing I can compare it to is it feels like when you are spinning your tires in sand and it starts hoping. On top of that, if I go over a speed bump slowly, my rear end has the "worn out shocks" feeling and will "bounce" 3-4 times before leveling out.

My question is, what in the world is wrong??? Are these shocks not stiff enough?

I am about to order some new ones, but wanted to get y'alls opinion first.

Thank you for the help in advance!

[equin]

Sounds like the shocks aren't tuned to the suspension. They may not be sufficiently damping the suspension's (rear leaf springs) oscillations. I have no experience with Rancho shocks or suspension products, but I've had really good experience with Bilsteins and Old Man Emu shocks.

Years ago, there was a tech at Bilstein named Shane who knew all the shock combos and applications for a variety of vehicles. I have no idea if he's still at Bilstein, but I found his number on their website when I last called. I'd give them a call and ask which shocks would work for your truck if you're interested in Bilsteins (which I highly recommend).

[duck'n]

Another vote for bilsteins...I LOVE mine!

[rebelangler]

I've got a set of bilstein 5100 series shocks that are perfect for your truck. I've got them on my ford and love them. They are used but only have about 5k on them..$100.00 for the pair

[mikeb1206]

If you did not get shocks for a raised truck that is your problem. Shocks are designed to operatate on the shaft at a predetermined height and if you have stretched the shaft further out you will get a terrible ride.

[Black Ice]

If you did not get shocks for a raised truck that is your problem. Shocks are designed to operatate on the shaft at a predetermined height and if you have stretched the shaft further out you will get a terrible ride.

This and another vote for bilsteins.

[rebelangler]

If you did not get shocks for a raised truck that is your problem. Shocks are designed to operatate on the shaft at a predetermined height and if you have stretched the shaft further out you will get a terrible ride.

His truck isn't lifted enough to affect the shocks travel on regular driving situations.

[StevenW]

This and another vote for bilsteins.

X2

[rebelangler]

Should have gone with the lifting coil over struts from bilstein instead of the leveling kit...just my .02

[CastAndBlast]

Thank you for the replies...

Rebelangler, thank you, but I think I am going to go ahead and order the bilstiens for the entire truck since it is about due anyways. 4 wheel parts gave me the part numbers that I needed for my truck with the leveling kit.

As for those that said it was due to the lift, my truck rode exactly the same with stock shocks before and after the leveling kit, but now has the washboard affect with the new shocks. I am not saying that it isn't due to the lift, but again, it is only 1" in the rear.

I have no problem ordering new shocks for this truck, I am just wondering what it is that causes the "washboard" effect? Is the shock too stiff, not stiff enough, etc.?

[banzai]

The washboard effect is due to too much compression damping. The springs want to compress with the bump but the shock is stopping it hard. The shocks have to be valved for the spring rate & weight of the truck for progression for compression and rebound and be the right length for the lift.

The bouncing after hitting a speed bump says that the shock cannot stop the oscillation fast enough to be good to your truck because compression and or rebound are not sufficient.

The place where you bought your truck did not take all of these variables into account. they sold you the best fit they had, but it wasn't close enough.

Buy shocks from a shop that knows suspension on modified vehicles but it will cost more. Usually this is not The Zone, but the guys that work at the Autozone are way-under-paid old school wrench spinners.

To save money, you can educate yourself reading online forums for off-road performance techs like TBH is for bowhunting. After doing your research, order your shocks from the lowest online seller like shockwarehouse.com.

[CastAndBlast]

The washboard effect is due to too much compression damping. The springs want to compress with the bump but the shock is stopping it hard. The shocks have to be valved for the spring rate & weight of the truck for progression for compression and rebound and be the right length for the lift.

The bouncing after hitting a speed bump says that the shock cannot stop the oscillation fast enough to be good to your truck because compression and or rebound are not sufficient.

The place where you bought your truck did not take all of these variables into account. they sold you the best fit they had, but it wasn't close enough.

Buy shocks from a shop that knows suspension on modified vehicles but it will cost more. Usually this is not The Zone, but the guys that work at the Autozone are way-under-paid old school wrench spinners.

To save money, you can educate yourself reading online forums for off-road performance techs like TBH is for bowhunting. After doing your research, order your shocks from the lowest online seller like shockwarehouse.com.a

That is what I needed to know! Thank you for taking the time to answer my question. It is greatly appreciated.

[banzai]

You are welcome. Someone explained it to me some time back and that is how we all learn.

Glad I could help, but all I did was point you in the direction of more detailed technical education.

Learn a little today and save some money. Learn more later, save more money by buying the right parts the first time on your future purchases.

Modifiying vehicles is a money loser from the start. All you can do is minimize the cash bleed-out by buying once instead of two or more times to build the truck you want. In the end hopefully you have a near-perfect vehicle for the task and you built it at a cost that is not possible retail. That when the $5000 redneck homemade wins over a $60k raptor in performance but not beauty or comfort.

[Cuz]

If you did not get shocks for a raised truck that is your problem. Shocks are designed to operatate on the shaft at a predetermined height and if you have stretched the shaft further out you will get a terrible ride.

True true.
But be careful with the Bilstein 5100 adjustable front shocks. When on the full 2" (maybe 1.5". Can't remember) setting they are rough as heck when off road. I have them now and am not impressed at all.