Hey guys well i need new shocks front and rear and was thinking of lifting my truck about 2-3 inches and I looked on American Trucks website and they have a block kit with torsion keys and shocks all around for pretty cheap has anybody run these things yet. Let me know whether it's worth it or not and if there has been any problems thanks.

 

If you don't mind a stiffer ride, add a leafs would be safer in the rear. You can accomplish the lift in the front by cranking your torsion bars.

 

im not as worried about the stiff ride as much as whether the shocks are decent or not. The way they are designed and the fact that they have poly mounts makes me believe they must be all right. Anyone else running this system. Im ordering it tomorrow and I guess I will let you know how it goes Ill take some before and after pics.

 

Remember guys, while cranking torsion bars may be cheap, it will alter your steering geometry and place your CV axles at an angle they weren't intended to run. Increased ride harshness will also result.

 

isnt that why they use torsion keys, so u dont have to crank them up. I realize the front end might be a little rougher but what about the shocks are they decent?

 

CV joints purpose in life is to run at extreme angles. You are not going to hurt them by lifting the front end a little. I would also dispute the notion that cranking the torsion bars degrades the ride. The exact same amount of wieght is on the front end, the spring rate hasn't changed, just the index point. The pitfall I see is that you are going to be very near the end of the shocks travel. The front end has very little travel to begin with and extending the shock too far will lead to clunking up front as the shock hits the end of its travel on fairly small bumps.

 

CV joints are not designed to run at extreme angles. Ask any Jeep Cherokee owner who has tried to run a lift kit and stayed with the CV style driveshaft. Granted you can get away with a little bit but there is a fine line there. The only true correct way to lift an IFS truck is to lower the front diff to keep driveline angles happy. I know the posts will come flying in that "I cranked my torsion bars and it works great" but I'm speaking truth here. Suspension is what I do for a living. Torsion keys will alleviate the ride harshness but will not address the steering geometry and CV angles.

 

Sorry, I have to call BS. Most serious off road rigs must go to CV style driveshafts to be able to run extreme driveline angles. In fact, if you do a Fab Tech lift on an Expy, you almost certainly have to buy their CV driveshaft to avoid vibrations. I drove one without it, I agree with their advice.

I find it extremely hard to believe you "do suspension for a living" and then make a statement about not running CV joints at angles too extreme for u-joints. Besides the fact that bumping and F150 a couple of inches is not going to result in anything resembling an extreme angle anyway.

Granted, 4-6 inch lifts will require the diff/axle to be dropped. 2 inches does not.

I am still waiting to hear your explaination on the stiffer ride too. Since you do suspension, I figure you can tell me how a spring the same rate with the same load is going to cause this poor ride you claim happens when torsion bars are adjusted. Tell me what the keys do to aleviate the harshness. That is just too funny. Nice to have an expert around.

 

I'm going to explain my experience. A little unbiased here because I still don't understand how these torsion bars work. Will look that up later.

I cranked my torsion bars and have noticed no change in ride stiffness, and this comes from driving on dirt roads daily while at home and not away at school. If it has changed then I don't notice it enough to bother me. Another thing is that I noticed that it's a little more responsive, I don't know if this is theoretical or not, on the highway just with little jerks left and right I noticed it dart instead of "sag" from side to side. Following me cranking the torsion bars I noticed while greasing my front end and changing my oil that my cv shaft boot, has ripped, only one side however. I don't know how long it has been open so I filled it with grease and then patched it up with rtv, to this day I see that the rtv is still there but I'm waiting for the first time I need 4wd to see if my shafts will hold up to it. Lastly, the clunk in the front that greenie mentions I believe I do experience, I've been wondering what this clunk has been and I thought it was play in my steering shaft.

As for flareside, I'd say go for it and see how it goes.

 

First of all I'd like to say I don't participate in the forums to inform people that they don't know anything about the job they have been doing for the last 20 years. I will turn the proverbial other cheek and keep this civil.

1) The term CV joint can have more than one meaning. The joint Fabtech refers to and most off-roaders (see the Jeep forums) are using is known as the Double Cardan joint. The outer CV joint on a Ford F150 or most front wheel drive vehicles is known as a Rzeppa joint. The Double Cardan can handle extreme angles, that's why they're used in short wheelbase rigs with extreme driveline angles like Broncos and Jeeps. The halfshafts in todays IFS 4X4's and passanger cars are not designed for these angles. It's usually the inner joint that will fail. Revtek had to start including spacers to drop the front diffs of Tacomas and Tundras down because their 3-inch coil spacre kits were causing inner CV joint failures. That's on a 3 inch lift. We have actually seen 88-98 GM K1500's with the inner CV joint broken off in the front diff because of maxed out torsion bars. This isn't my opinion, this is fact. See attached photo for picture of Double Cardan CV.

2) A torsion bar is a spring. When you twist the bar (that's what you're doing when you tighten that adjusting bolt), it has less give. It is the same as installing a stiffer leaf or coil spring. Some people have different tolerance levels when it comes to ride hashness. I have an emplyee who maxed out his torsion bars on a 95 GMC Sierra. That ride sucks but he doesn't care because he got 33's on it without spending 2K on a lift kit. Torsion keys will help alleviate the ride harshness because they re-index the torsion bar meaning you get the ride height change without so much "twisting" of the bar. I am not a big fan of the keys as they do not address the other areas.

3) When you increase ride height you are changing the angles of the steering linkage. This is why complete lift kits include the necessary pieces to lower the steering linkage to retain O.E. geometry. Otherwise you have what's known as bump steer.

Bottom line--do whatever you want to your truck just please be aware of the ramifications. Fair enough?

 

Sorry...Still wrong on the torsion bars. How do you figure you are "twisting" them more if the amount of wieght they support is the same as before you turned the adjustment bolt?

The keys simply allow more adjustment, they have no effect on the spring itself. Just as cranking on th bolt has absolutely no effect on the spring stiffness. That is as rediculous as saying if you crank the front end down via the adjustment bolt s the ride is going to get all soft and squishy. It isn't because no matter where the bar is turned, it still has the same spring rate supporting the same amount of wieght.

If you add a heavy bumper and a winch, then crank the bars to get the ride hieght back, now you have twisted the bar, now your ride is likely to change some.

The other contention seems to be that a Rzeppa style CV joint can't endure the increased angle you are going to see by lifting one of these trucks 2 inches. They are designed to run smoothly at greater angles than u-joints, that is why they are used period. Certainly any style joint is more susceptible to damage when running at an angle. The real world part of this is we are talking about weak engined trucks with open front differentials. There are a precious few of us running with low range and big tires regularly. It simply isn't an issue, unless you want to continue making it one.

20 years experience and you have to come on and throw out warnings that don't even apply to the situation.

 

Big Greenie, I really don't know what I did to offend you but I'm not basing my replies on emotion or opinion. I fix this stuff on a daily basis. One guy wants to crank them the next doesn't. To each their own. I thought these forums were supposed to be a friendly place. Looks like that's the one thing I was all wrong about.

 

Im new in this part of the forums, but I just recently got a 98 f150 so i was reading up on some of the common problems and just getting a little more familar with them and came upon this post. My buddy has a 90 GMC that we cranked the torsion bars up on, and we took it on a test drive and it rode TERRIBLE. Going down a smooth rode at 35 mph it was bouncing down the road. As soon as we got home we lowered them some, but left them cranked quite a bit. Now granted this is a older truck compared to ours but it is still the same design. About 2 months later one of his CV joints busted, and then about 2 weeks after that the other one broke.
In the mean time of this I cranked them up on my dads 02 f150 about 1" since he wanted to run slightly bigger tires. He got it aligned about a week later and it rides rougher than it did before also. He describes it as a more "choppy" ride. Now his truck is making some sort of vibration in front that is very noticable just driving down the road. Im not trying to side with one person or the other but, this is just my opinoin on this subject. I just got my 98 and as for me, Im not going to lift them any even though I would like the lift, but the possible effects of this turn me away.

 

Could just lift a 2wd and not worry about the Rzeppa joint.

 

It's generally not the Rzeppa (outer) joint that fails, usually the inner plunge style is the one that gives out.