Front lift springs are very stiff

[WJACKSON11X]

Installed 3" TC Ez rides (new) on the front of my Burb (couple of months ago) along with some used TC shocks that were on my Jimmy. I have noticed that the front rides very stiff. When going over small speed bumps, it is quite jarring.

I did notice that I tightened down the front spring bolts a little too much and actually bent the hanger in like this \ /. Not quite that bad, but you get the idea. I wouldn't think that would cause the issue, but just wanted some opinions.

I had 4" TC Ez rides on my Jimmy, but don't remember them riding that rough. Any ideas?

Is it possible that the shocks are shot out and causing the rough ride?

 

[76k5blazerr]

It is quite possible that your shocks are causing the rough ride, get you some bilstiens.

 

[dyeager535]

Is it possible that the shocks are shot out and causing the rough ride?

Not likely. Most shocks are biased much more towards rebound than they are compression. Quite common for standard shocks to be 30/70, 30 being the compression number.

Can't help with those particular springs, but I've got factory quad shocks on mine (which are old tech and probably don't help as much as a single good modern shock) and it rides good.

If the shocks were shot, then the springs would actually be easier to flex to a degree, and you'd get a pogo-effect when you hit a bump.

Did you throw new tires on at the same time? Tried playing with tire pressure? My BFG's ride relatively rough at 35-40PSI, but when aired down (especially around 20PSI) the ride is exponentially better. Enough that I no longer drive offroad with the tires at full pressure. Doesn't help road manners, but it is a much larger factor with my tires than I expected it to be.

Edit: this of course assumes you aren't bottoming out when you hit bumps, but that's pretty unlikely with 3" lift springs I would think, at least under normal driving conditions.

 

[WJACKSON11X]

I was running BFG KM2's and recently switched to BFG AT's. Didn't change the ride in that aspect. I will lower pressure and see if it changes. It almost like the springs just aren't flexing enough though. I can stand on the front bumper and jump up and down trying to flex, but not much. They may just need some time to soften up a bit. They flex ok offroad.




I have aftermarket bumpstops, but are not even close to touching.

 

[dyeager535]

Mine are BFG AT's as well, I'm really surprised at how rough they ride. I recall looking at the load range d or e's that my Dad had on his truck (My BFG's are load range C) and I noticed that the BFG tire appeared to have a lot more reinforcement (belts and ply) than his did. At 20PSI you can only slightly tell the tire is low, and IMO that indicates the sidewalls are very stiff.

The tires aren't going to completely make up for the spring stiffness, but they might help a bit, if you can lower pressure without affecting wear.

Someone should be along to comment on how stiff those springs should be though. I'm sure others have run them.

 

[diesel4me]

Tires make a lot of difference on stiffly sprung vehicles..


I think the reason GM used tall profile tires on 3/4 and 1 tons was for the added cushioning effect from the taller sidewalls--they help compensate for the stiff spring rates...(which are even worse with aftermarket lift kit springs)...

My K2500 would have came factory with 215/85/16 or 235/85/16 tires,which are a high profile compared to a 75,70,or 65 ,60 series tire..

I have run a set of 245/75/16 tires,load range "E" and thought they rode pretty good,then I got a set of 265/75/16 tires ,also "E" rated,and it rode a lot better,though my gearing did suffer some and it kind of hurt the power and acceleration some..

When I borrowed a set of four 235/85/16's from a friend,I was surprised how much better the truck rode over bumps and handled--they were also "E" rated and fairly new,with deep tread...(I borrowed them to get an inspection sticker ,till I was able to scrounge up 4 better tires for it)...it was probably the best its ever felt as far as ride and handling..

I have had a set of Goodyear Wranglers ,265/75/16's on it that were load range "C" and the truck felt like it had four gumballs on it--it rode somewhat smoother,but had mushy handling and some rear side sway going over rough roads..I think the stiffer E rated tires actually rode better..

I also had four 205/55/16's I had on 8 lug rims I just used as rollers ,for the hell of it one day I put them on the truck and drove it...the diffs were maybe 3" off the ground,and my plow frame gouged the crap out of a hilly driveway..it had great acceleration though!--too bad it rode like it was on rims only,the ride was horrible!....those came off the same day..kind of sucked because they were nice "Blizzak" snow tires that gave great traction..

I've taken shocks off more than one 4x4 that were almost completely seized up inside,and made the truck ride like it had dead axles..the ride improved considerably after they were replaced--but most shocks dont offer much resistance on compression,they just control the rebound,keep the tires on the ground and not bounce or wheel hop...unless the shocks are seizing up inside, they probably wont make much difference when hitting a bump..

 

[Greg72]

Didn't read all the responses, but a simple test to isolate the problem is to just unbolt the shocks and take a quick drive.

If the springs don't get any softer it's not a shock issue. If it gets a LOT softer, it's time to look more deeply at a shock issue (wrong length, too stiff, etc)

-G

 

[Blue85]

Also try disconnecting the sway bar and go for a ride. Unless you use disconnects, the sway bar binds with lift springs.

 

[K85 Octane]

agree
sway bar removal and shocks
also make sure those bushing aren't binding now that your mounts are \/
I have the HD 4" but also have a lot of bumper weight, they feel fine.

 

[Phil513]

On the advice of the guys here, I chucked my sway bar.

Life immediately got better.

 

[Greg72]

I did notice that I tightened down the front spring bolts a little too much and actually bent the hanger in like this \ /. Not quite that bad, but you get the idea.

Are you talking about the front spring eye, the rear shackle area, or the U-Bolts that connect to the axle?

The bushings are supposed to have a steel insert that allows you to torque the bolts down without distorting the bushings or hangers.

Do you have greaseable bolts (yet)? Being able to occasionally pump a bit of grease into those steel sleeves helps insure that the bolts/bushings will actually rotate instead of trying to flex and tear the bushings apart when the spring flexes.


-G

 

[WJACKSON11X]

I forgot to mention that I have crossover steering, so no swaybar. I will try to remove the shocks and see if that changes anything.

I will also lower the tire pressure and see if it changes the ride any.