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SWLA
07-12-2002, 21:06
Just curious, but is there any way to raise the front of the truck a few inches without cranking the torsion bars or getting a full lift? I seem to recall reading somewhere about a kit that raised the front end but did not require adjusting the torsion bars. I have also heard about some guys with 1500's using ford torsion bar "keys" to level the front end. I would like to have my truck as close to level as possible, but not at the expense of ride quality.

SoCalDMAX
07-12-2002, 23:27
SWLA,

I've seen 3" spindle lifts, but they're a little pricey.

I don't know how the idea spread, but turning up the torsion bars (even to the end of the adjustment) will not hurt the ride at all, from personal experience.

If you look at the front snubbers, the truck is sitting on them right now at stock height. So the torsion bars and the snubbers (even tho very soft) are both supporting the truck. It should not be sitting on the snubbers, it should have a decent amount of travel before the snubbers gently stop the travel.

My DS is cranked up around 8-9 turns, PS cranked up about 5-6 turns (all of these trucks sit a little lower on DS) and the truck sits fairly level. The dealer finished leveling it for me, then did the alignment. If you jack mine up, the suspension still droops, indicating still more travel left. The truck still rides too soft in front, much firmer in the rear. I have the RS9000 shocks adjusted to 4 in front, 2 in rear to try and balance it out better.

Try complaining to the dealer that is sits on the snubbers in the front and truck is not level from side to side. They might level it for you with a free alignment, it worked for me. ;)

Regards, Steve

gardnerteam
07-13-2002, 06:45
You are referring to the Hill Front end leveling kit. I bought one for a customer vehicle and was about to put it on when he decided to go with a 4" lift because he wanted more lift to get 295 tires under. It consists of 2 new torsion bar keys slightly configured at a different rate so as to give you a level heigth without adjusting. It gives you the nice factory delivered ride, level vehicle, all without screwing up the torsion bars. Screwing up the torsion bars did affect the ride in his case and he wanted the better ride. But, he decided he needed the lift to get 295 under. Since the leveling kit is new and unused, I will either return it or sell it and pay the freight. Sells for $149.

NutNbutGMC
07-13-2002, 06:51
^...IMHO, you'll have much less of a sacrifice of ride quality by tweaking the torsion bars, than by adding a modification kit of any kind.

Billy14
07-13-2002, 09:21
I installed 295's the day I picked up my truck. Only had to tie back the plastic wheel well skirt on the driver's side at the washer bottle & emergency brake cable area (driver side only).

Never hit even with some pretty serious 4 wheelin. Did the torsion rod routine before installing the Ranch Hand replacement bumper to level the truck out. Dealer cranked em up all the way to the stops & the truck now sits about 1" low in the front. There is no question the truck rode rougher but softened up with the added weight of the bumper.

Billy

hoot
07-13-2002, 09:48
You guys have to understand, turning up the torsion bars doesn't cause them to be tighter. It simply raises the truck. The same effect as putting a spacer under a spring. The spring isn't compressed more, the truck is sitting on top of a spring and spacer with the spring still being compressed the same. Dodge lifts use this method.

With torsion bars. You twist the bars, the truck goes up. The clock position of the front of the bar is still the same relative to the rear of the bar only the whole bar is turned. The only thing you lose cranking up the bars is whatever amount you crank up, you lose that much downward travel.

You don't need any kit to get your truck level and GM even promotes the fact that you can adjust ride level with the torsion bars.

The older pre-99 C/K's didn't work well when jacking up the front because of the design didn't accomodate much. They redesigned the HD suspension in 2001.

[ 07-13-2002: Message edited by: hoot ]</p>

mackin
07-13-2002, 10:03
hoot,

I cranked my 98 up 7- 8 turns ,hit a monster pot hole ,busted the shock...... Opened the upper ring right open ......I do see the top shock mount are different on the new front ends..... To be safe on my 01 ,I cranked it only 4 turns,being a woosie...... I would like to go up to 8 like my 98 ,but not looking for problems .......

MAC smile.gif

NutNbutGMC
07-13-2002, 11:13
^.... Can't agree with hoot. Torsion has a definition and by that, I have to disagree, but it doesn't really matter. It's a mechanical concept that is at the simpliest and least effective stage. If you lose downward travel, you lose that much spring rate travel, thus a stiffer ride. "Nuff said 'cause I don't care.. :D
Hell, try sticking a wedge shaped 2 x 4 block in there :D . Remember, one on each side for symmetry.

LMAO at Mack Daddy... the now self-proclaimed WOOSIE..... LOL....LMAO....

MACKIN' IS A WOOSIE.... &lt;==== He says so himself... :D :D :D

[ 07-13-2002: Message edited by: NutNbutGMC ]</p>

hoot
07-13-2002, 11:42
Mackin,

These trucks all have travel limiters in the suspension with shocks that have enough travel for the entire sweep. There is no reason cranking the bars would cause a shock to break. All cranking the bars does is repositions the suspension more downward, closer to the downstop.

NutNbutGMC,

Torsion is simply the twist imposed on the bar when restrained at one end and turned at the other. When you crank your bars up you are raising the truck at the same time. The bar is still twisted the same amount. The result is a higher front end. Now if the truck didn't go up, then the bar would be twisted more.

The only possible change in torsion loading is the fact that with the front raised and suspension in a more downward position, you would now have more upward (compression) travel before you hit the upper stop. Now that will twist the bar more than stock on a very hard compression event. That doesn't happen very frequently in moderate driving conditions.

et
07-13-2002, 11:47
gardnerteam,

I am in The Dalles. Please contact me at e j s c o t t@skyride.net. On edit, I placed spaces between my email name to keep it from being deleted. I am interested in your Hill Kit.

[ 07-13-2002: Message edited by: et ]</p>

mackin
07-13-2002, 12:32
hoot ,

Well the way the Eye on the broken shock looked made me believe the travel went farther then the shock would alow..... It was a monster pot hole .......


NutNbutGMC,

Oh crap forgot you was watching ...... Dam, I'll live it down some how....... Woosie on the way up^.........

MAC :D


Definition =&gt; Torsion bar suspension uses the flexibility of a steel bar or tube, twisting lengthwise to provide spring action. Instead of the flexing action of a leaf spring, or the compressing-and-extending action of a coil spring, the torsion bar twists to exert resistance against up-and-down movement. Two rods of spring steel are used in this type of suspension. One end of the bar is fixed solidly to a part of the frame behind the wheel; the other is attached to the lower control arm. As the arm rises and falls with wheel movement, the bar twists and absorbs more of the road shocks before they can reach the body of the car. The bar untwists when the pressure is released, just like a spring rebounding after being compressed.

Adjusting the torsion bars controls the height of the front end of the vehicle. The adjusting bolts are located at the torsion bar anchors in the front crossmember. The inner ends of the lower control arms are bolted to the crossmember and pivot through a bushing.
======================

I would think it would tend to be a little stiffer after the adjustment ... NO? Because with adjustment aren't you pre loading the bar to gain height?

[ 07-13-2002: Message edited by: mackin ]</p>

hoot
07-13-2002, 13:55
No you are not preloading the bars to gain height. The truck is no heavier just because it's higher. There is the same amount of weight putting the twist in the bars. The bars twist the same amount.

This is my last try...

Both ends of the bars are hexagon and fit into hexagon holes. In the front they go into hexagon holes on the lower control arm. In the back they go into hexagon holes in the adjustment cam. The cam is a slab of steel with a hexagon hole on side and an threaded hole with the adjusting screw in the other side. By tightening the screw, you rotate this cam which in turn rotates the back of the torsion bar.

When you rotate (twist) the back of the torsion bar, the front rotates the same amount because the only resistance to twisting is the weight of the truck, which in this case is constant. Since the weight of the truck up front isn't changing while you twist the back of the bar, the truck rises and the torsion bar still has the exact same amount of twist in it.

Maybe I can get some help in this explanation????

SoCalDMAX
07-13-2002, 14:27
The only way I could explain torsion bars any differently would be to say that the spring rate of the bar is dependent on the characterics of the bar - thickness, material, etc. The only way to make the suspension stiffer is to change the torsion bars. The suspension compresses and rebounds based on spring rate up to the limits of its travel. The truck comes delivered sitting nearly on the end of it's travel, the snubbers.

As you turn the bar, it merely raises the front end. If you turned the bar and the truck did not gain more travel because it was already at teh limit of it's travel, then you would be pre-loading the suspension and making it stiffer.

The fact remains, as delivered, my truck rode over speed bumps (compression stroke) as if it only had a few inches of travel. Which it did, sitting on the snubbers. Now, the suspension has more compression travel before hitting the snubbers and end of travel.

If you think about it, the torsion keys do the exact same thing that the adjuster bolts do. They merely turn the torsion bar, but without turning the bolts. The bolts do the same, it's just that the new keys are made at a different angle, that's all.

If a shock blows out hitting a pothole, it just couldn't take the forces imposed on it based on the speed (MAC speed? Never!) and size of the pothole. If the truck was raised, the shock could not have been compressed too far, it was expanded farther than normal. Hold your hands 18" apart. That's the shock at stock height. Now hold them 20" apart. That's the shock on a truck lifted 2". The ends aren't closer, they're farther apart.

Regards, Steve

NutNbutGMC
07-13-2002, 18:41
^......Hoot, with all due respect, you're preaching to the choir. I have a Ph.D. in Mech Engr.so I slightly understand torsion, however I respect your take on the specific machine application. I'm going out to my new garage (40' x 40'), crawl under this thing and study it some more.
Anyhoo... This has been fun, any way ya' look at it and there is always room for more fun... It's a stinkin' truck (well, MAck Daddy's anyway, up until today)... :D I just want more speed.
All of you guys are great and know way much more than I even want to .....
Mackin, you rock the house.
SCDM... You are way West for my comprehension. I'm just a fat old hillbilly, in East TN.
Hoot, we shall bond... Our tags are the same. :D and ya' can't miss on that.

SWLA.. See what you got started? And you made Mackin come out of the closet to expose his self-proclamation....of being a Woos... LMAO :D

You guys are great. Now, back to the drawing board. Pics of the new garage as soon as it is completed and presentable. I need a lift for the center bay, now.

[ 07-13-2002: Message edited by: NutNbutGMC ]</p>

hoot
07-13-2002, 20:43
PHD..... Piled Higher and Deeper ;)

SWLA
07-14-2002, 10:46
Ok y'all, thanks for all the input. I understand what you're explaining as far as torsion goes, but 2 questions. Why do most folks complain of a subjective decline in ride quality after adjusting the torsion bars, if it isn't front end travel, what could it be? Why does cranking the torsion bars require a front end realignment, or how does it throw the front end out of whack?

SoCalDMAX
07-14-2002, 18:04
SWLA,

I have a theory, and it may be wrong. A lot of people might be adjusting their torsion bars to gain height for taller, wider tires. They're heavier, especially if mounted on large cast rims.

Any time you add unsprung weight to a vehicle, the ride will be rougher (all else being equal.) Thus a Cadillac rides smoother than a Yugo due to it's greater ratio of sprung to unsprung weight. The car outweighs the rims/tires/brakes/hubs by such a large ratio, it glides over the road as the tires/etc react to the road surface.

The alignment may be necesary depending on how far you crank them, think of it like the truck was delivered to you as a lowrider. You're now removing the dingle balls and returning it to a more appropriate height. And the camber might have changed slightly in th process. ;)

If you aren't sure if you'll like the truck with the torsion bars turned, just use a good sized breaker bar and turn the bars a few turns. Take it for a drive for a few days. If you honestly don't like it, turn it back. It only takes 5 minutes each way.

NutNButGMC,
No wonder you're having trouble with this, you're too well edjimacated! Just remember, the end attached to the A-arm is free to rotate... ;)

At the very least, we got it in writing from Mac himself that he's a woosie! THAT's priceless!!! :D Worth WAY more than $16/yr just for that 1 post!

Regards, Steve

[ 07-14-2002: Message edited by: SoCalDMAX ]</p>

hoot
07-14-2002, 21:38
The complaining was with pre-99 trucks. I don't hear anyone complaining after raising the HD's. The ride quality on my truck after 5 turns did not seem to change at all.

Listen!!!!!

These trucks are different then the pre 99 C/K trucks!!!!

Listen!!!!!

Cranking the bars only raises the truck, it does not preload the bars any more than they already are stock. Personally I believe you would run out of threads on the adjusters before you effected ride quality.

The suspension has different geometry and the travel stops are totally different.

Man you guys are thick ;)

D-n-Tyke
07-15-2002, 08:36
From what I have seen the Hill Front end leveling kit are the same keys as the F*#D keys. Only $100 more expensive. Here is a link to a picture with an overlay of a F*#D key over teh Hill key. You make the call.
http://www.members.aol.com/xofmot/keys.html

CAVdmax
07-15-2002, 15:39
A reason why a person may associate ride quality suffering with torsion bar adjustment is if they tightened them excessively (or the shop that they asked to do it did) so that there is no down-travel in the suspension and the springs themselves are, in extreme cases, actually pre-loading against the down stop of the suspension thereby making it more resistant to up-travel.

I recall once watching a worker at a local tire store use a pneumatic impact wrench to tighten a customer's torsion bars after installing over-sized tires. This effectively eliminated the front suspension completely and of course the ride suffered greatly!

A moderate amount of adjustment of the torsion bars which still allows the suspension to have sufficient up and down travel will not affect the ride quality under normal circumstances, however.

GMC D-Max
07-15-2002, 17:00
The reason the ride quality would suffer is because the geometry changes significantly when you crank up the torsion bar adjusters. The front end doesn't react as smoothly to bumps and potholes, because the front end doesn't move in a more linear up/down direction as "stock" height. The front wheels try to move more "sideways" after cranking up the bars.

I cranked my adjusters 4 full turns from stock (as delivered), and the ride got noticeably harsh and rougher. I backed off 1 turn, and it's quite a bit more tolerable. I've got 285/70-17's (33x11.25) under it, and only have a very slight rub on the plastic at the back of the wheelwell at full steering lock. Didn't have to trim the airdam, either.

I, too, looked at doing the leveling kit, even thought about making my own cams (I'm a machinist by trade), but decided the height/ride was a good compromise. Maybe someday I'll put a big lift on it, but not as long as I'm using it to haul an 11'+ camper.

[ 07-15-2002: Message edited by: GMC D-Max ]</p>

hoot
07-15-2002, 17:58
The cams do nothing but give you more adjustment on the screws, am I right?

So what's the point? You only have so much suspension travel. Is this leveling kit a gimmick?