I would like to share my experience with everyone, regarding the front end ride and control problems encountered with torsion lifts, including the green keys people are using. I am so impressed with the results of my improvements you all should consider this.


So many people are lifting the truck with torsions, OK, we'll not have a debate on the health of doing such, I am going to limit this thread to stating how it can be done without losing that IFS quality ride so many people put stock in. So far, everyone who has lifted with OEM shocks or OEM bilsteins, has complained af the pogo ride induced in the process, and even the bilsteins do not solve there problem. I have dived into this, read 100 such accounts and set out to reverse engineer the causes.


1. In stock, unlifted configuration, the wheel has a 2 1/2" down travel capability. More or less fact, easily reproducible in the driveway with a jack.


2. At full extension, the shock limits downtravelhttp://www.dieselplace.com/forum/smileys/Question.gif Can't tell you why the engineers did this, but I will conclude that with this design, they did not anticipate torsion lifts. At full extension, the downward travel stop is not at its limit, in point of fact, the bilstein shock (and stock) limits extension so much, that there is still 2" of wheel downtravel left in the stop, when the wheel is hanging from the shock.


3. If you lift the truck with torsion, (green key or stock keys, it makes no difference) and lift it 2 1/2", you are now going down the road with absolutely zero rebound (downward) travel capabilty. When the road falls out from under the wheel as in a pothole, that wheel is not going to extend, and that wheel is going to crash into the other side of the hole, with the full weight of that diesel behind it.


4. Folks who put green keys in and torque past the point of running out of height, will say, "I still have 1/2" of space to the downward travel stop" This is funny. With green keys, it is actually possible to torque the torsion bars to the point of bottoming the OEM shocks, and more. A person might get under there and disover that for some reason, the truck is "just not going up any more", but "I'm not bottomed out". Everybody needs to know, the bilstein OEM are almost worthless with this torsion lift. And bilstein knows that we are doing this, they even say go ahead, 1-2" no problem, shouldn't matter. BS, they sell shocks. I'm not bashing green keys, or bilstein. Just be aware.


5. If you ride with the shocks topped out, cornering will suck. The inside wheel looses traction as it lifts off the ground, and I would bet makes the vehicle more of a rollover hazard, when compared to a truck with 2" droop capability. Don't bash me here please.


What I did was lift my truck 2 1/2" with my H2's and bilsteins. I got what you all got, pogo crappy ride, and lowered it 1/2" or so and saw that some of it was recovered. This pissed me off, cause it was still crappy and I needed to know why. Got the jack out and started playing and made the discoveries numbered above.


Knowing these shocks were so well revered, I decided to MAKE them work and solve my ride deterioration at the same time, and even improved the front end ride over stock, I believe.


I decided that I needed that 1-1/2"-2" of downtravel that the shock prevented me from using. The spacer was easily fabricated from Home depot 1/4" aluminum bar. 1/2" total. Get new SS bolts as well, 1/2" longer, use a thread lock compond to keep them from backing

http://www.dieselplace.com/forum/uploads/69A_washers.png


Shows the 1" of washers to shim the shock down.

So far, everyone who has lifted with OEM shocks or OEM bilsteins,





It would take more shocks then there is room for to lift the front with a shock! How many shocks do you have?http://www.dieselplace.com/forum/smileys/Confused.gif


You also stated that raising the front 2-2.5" produces a crappy ride. I want to know by who`s judgement. Because Some of us was after a stiff ride. I would not like to ride in a stock truck cross country due to the soft ride. But I could ride in one like mine all day every day.


So what is crappy to you, may be the best ride in the world for others.Edited by: hdmax

Mike,


The truck is not lifted with shocks, it is lifted with torsion bars, it is dampened with shocks, my apologies if I did not come clear.


I will say that I really dont enjoy having my accelrator go halfway to the floor in feedback loop caused by no downtravel. This is reduced now.


You have taken one sentence (fragment) out of context. There is no way that a 2 1/2" torsion lift ride on oem shocks can be considered comfortable. It is just plain annoying, like having the chicken pocks!. But reading your response, maybe you did not understand my article. I use ONE shock.

Are you lifted with torsion bars or torsions keys?

Masterp2,


Great idea! Thanks for sharing!

Are you lifted with torsion bars or torsions keys?


I don't know if you were talking to me, but I have the keys, not that it matters, as either way produce the same thing. It is just that with re indexed keys you can go to a more extreme lift.


When I tried to adjust the torsion bars with factory keys in place. I was unable to get more then about 3/4" of lift. Now with the replacement keys I can not get less then about 2-2 1/4" of lift. I had to use loctite on the threads and screw them in just enough to keep them from falling out.

You have taken one sentence (fragment) out of context. There is no way that a 2 1/2" torsion lift ride on oem shocks can be considered comfortable. It is just plain annoying, like having the chicken pocks!. But reading your response, maybe you did not understand my article. I use ONE shock. I have about 2-2 1/4" of lift on the front end, and I like the ride. That is my opinion. If you say you do not like it, then that is your opinion. NOT FACT! just your opinion. So how did I take your sentence out of context? I simply gave my opinion. I did not tell you that you liked the ride, so don't tell me I can not like the ride.

Mike, I think you keep missing my point. The ride I don't like is not caused by torsion lift, but the resulting shock travel restrictions. This was meant to help people solve a problem, you clearly don't have one.http://www.dieselplace.com/forum/smileys/Clap.gif No problem

Rancho makes a 1-2" longer 99000 for this application. Edited by: The Original Diesel

Rancho makes a 1-2" longer 99000 for this application.


That is what I was told by them, But when I ordered them, I got the factory size shocks. When I complained about my order, I was told that the next size up was for the 4-5" lift. And that they did not have them in 2" longer size.


So I don't know what to believe.

Bilstein has a short extension available as well. I haven't tried them personally, because I like the way mine rides. I'll likely try a set though just to see how they work.





P.S. The "party line" at Bilstein is that there is a "top out" damper inside the shock which keeps them from pinging if topped out.

HDMAX


Fortunately you are happy with the ride they provide. that could be the answer why you are, ya think? Did you compare the extended length of the shocks before installing? I think the OEM 9000 is longer, not 100% sure, but if so, it would explain why you didn't empathize with my ride problem solution, in that you may never have experienced the problem if you don't have an oem sized shock on a lifted vehicle.


Even a half dead longer shock would be better on a 2.5 lift than the oem bilstein brand new. (just my opinion)Edited by: masterp2

Kennedy


Now you tell me.http://www.dieselplace.com/forum/smileys/Angry.gifEdited by: masterp2

Masterp2,


I think it needs mentioning that GM did the same thing at the rear. The stock shock limits the downward travel there too, as can be verfiied with a jack. If you order the stock height RS9000Xs, they will have IIRC about 2" longer extended length.


Thanks for posting. I know what the next project is. (After the airbags go on the rear)http://www.dieselplace.com/forum/smileys/Big Smile.gif


Jeff

For 2" longer REAR shocks order part# RS99297.


They are made for the Rancho 4" lift kit. The Rancho 4" lift kit only gives you 2" of lift on the rear using blocks and u-bolts just like what I did with mine and many others have done.


I extended the rancho rears as I was installing them and no way in hell they're topping out! They have to be compressed fairly far to bolt them in.

Pulling the overloads made the rear a non-issue, lowering it an inch, only to be restored by airbags. I'm getting ready to do that to and maybe remove one of 4 leafs. That back end is just too hard, now that I'm getting spoiled on the front.

Thanks for the tip, masterp2! http://www.dieselplace.com/forum/smileys/Clap.gif


My truck has torsion bars raised to about 1 1/2" (maybe 2") above stock height, plus with Timbrens in front. By adding 1/2" spacer on the bottom, and 1" spacer on the top, it should bring the shocks back to the original position, which should allow the shocks to work better. http://www.dieselplace.com/forum/smileys/Cool.gif

Keep in mind that the CV joints may bind at full droop with your 2inches more down travel.

The down travel is limited by the bump stops in the position that GM designed them. Dunno why they made the stock shocks so short but that would be pretty silly if the bump stops aren't able to touch without binding the CV joints.

wxmn6


What are your impressions of the timbrens (empty ride quality)? Have you tried shimming them down to the a-arm and observe ride quality difference?Edited by: masterp2

I have the Timbrens because I run a snowplow on my truck. It does help with extra weight on front, making the truck more stable and safer. Also it help reduce the front end drop when raising the blade. The Timbrens always are in contact (slightly) with the A-arm when the truck is on ground, so there is no need to shim it around. There is not really much of a difference in ride quality when empty, I just do not notice it. I like it pretty much but it is just that I raised the torsion bars to make the truck level, which cause the shocks to become less functional and I just want to bring it back by adding the spacers as you suggested in the beginning of this thread. Edited by: wxmn6

I didn't realize the timbrens were longer than the jounce. They must be if yours are touching with a 2" lift. Hmmm. The jounce is 1/4" off the a-arm in the 2" lift.

masterp2,


After making these modifications, have you noticed anything now that you would have done differently? I am getting a set of H2 takeoffs (when the dealer gets a set in), and I am planning on doing this mod and adding air bags to the rear. I am also adding green keys, and cranking them up so I get about 2" of lift, maybe less if the wheels and tires fit okay with trimming (I'm planning on putting 285/70's on the H2 wheels).


Thanks,
Dennis

what are timbrens?

Dennis, i would recommend you forget about "green keys". The stock keys will provide more than enough lift, up to 2.5 inches approx. It is a waste of money in my opinion. (also you are stuck with a "lifted" truck with no down adjustability)


Anything over 2" and you start losing a lot of articulation as you approach the downward travel stop (using shock mods). For ride comfort, it is important to keep 2" of downtravel, and 3" of compression capabilty. A lot of trimming and tie backs with the 315's and 2". A lot more trimming/cutting at 1", but better ride characteristics.


I don't know if you are aware, but I removed the bottom leaf and flipped the overloads after taking some arch out of them (overloads). This is a noteworthy spring rate reduction and empty ride improvement, BUT, and especially since you are considering the airbags, the thing I would do different is


1.) re-arch the reduced spring pack so that stock ride height is attained at 0 psi, then fill to 5-10. The bag needs about 7" to operate in the reduced spring rate area. Removing a leaf, leaves the truck down about an inch or so, and ride comfort is lost when inflating the bag to 20 or more psi to restore stock height.


http://www.dieselplace.com/forum/uploads/744_airlift_data.png


When the airbags are at 5 psi, at 5", you can see by riding the bottom curve (airlift SD data), you quickly go from 300 lb/inch to over 2000 lbs/inch with only a 2" compression, and that's tooo much for empty ride comfort, but at least it's progressive, unlike overloads. Get the bag up to 7" design height at 5-10 psi and you get another 1-2" of smooth low spring rate before the curve rises. The trick is to keep the spring pack rate down. More arch, that's what I think, that also keeps the truck off the inverted overloads more of the time. I have also played with the idea of putting polyurethane botton type stops on the inverted overloads, so the overloads don't feel so much like stops. I know when I run 10 psi, my spring pack does interact occasionally with the overloads (empty). De-arching the flipped overloads is something I would not do again, unless I did not have airbags.


or


2.) use the firestone 9000 series sleeved bags instead in a custom install. No kit is available for our trucks in the bump stop location for this bag. I have been really tempted with this (but I'm tired). The advantage is that you don't increase the spring rate of the bag so much when inflating it. They do make a kit that mounts on the leaf, and uses the bump stop to protect it against overtravel self- destruction. Worth considering if you don't mind drilling brackets into the frame.


KEEP IN MIND, ALL THESE REAR END SUGGESTIONS ARE CONSIDERATIONS FOR IMPROVING EMPTY RIDE ONLY. They possibly lose some value the more you pull a load. if i were hauling 5-10K every day, i would not remove a leaf, i would flip the overloads and add the super duty bags. The moment you remove a leaf, you nullify the manufacturers haul numbers and run on assumed risk, with no test data protecting you. Side to side lateral stiffness must be weighed as a con when doing what I did, and let's face it, it's important to keep the trailer behind you.


Sorry about the long post.

Michael,


Thanks, great info. Since I tow at the limit every now and again, but don't offroad much at all, here is what I plan to do:


Rear: Put on the Air Lift Super Duty. Leave the rest of the rear alone.


Front: Do your shock mods (1" of stainless washers at top, 1/2" aluminum block at bottom). Crank the stock keys up.


Tires/Wheels: H2 take-offs with 285/70-17s. I'll tie/cut as necessary, but hopefully won't have to, too much.


If necessary: Swap shocks out, Bilsteins in front, RS9000s in rear


If necessary: Swap for 'green' keys.


What do you think? THANKS!!!
Dennis

I would say it's a good plan. But if you haven't already done it, consider just flipping the overloads, it such a dramatic ride improvement, most people are so impressed when their kidneys get a rest. Easy to do in the driveway WITHOUT removing the springs. A good hydraulic jack under the hitch is all. Can be done in less than an hour. Having the airbags and overloads is a bone-jarring redundancy.


The 285's is a smart idea, an easier time for sure. I sold my stock wheels/tires for more than the H2 combo, and the 315 actually fit in the spare location, JOYhttp://www.dieselplace.com/forum/smileys/Hug.gif I like what the 315's do to keep the RPM's down on the highway, Quiet.

Michael,


Have you called Deaver Spring to talk to them about creating a set of stock height spring pack that will keep your load carrying capability and soften the ride yet? I called them and they said they could make a setup up but a one off would cost a bit. I am thinking if we could get enough people on here to put together a group buy or something Deaver may be interested in starting to manufacture them on a reg basis. The make a 4inch lifted spring pack and sell it for around $500. Any thoughts about going that route?


http://www.desertcommunication.net/deaverspring.html
Edited by: se7enracing

Michael,


Okay I forgot one part. When I tow, I am planning on swapping back to the stock wheels/tires. That's why I don't want too much lift, otherwise, I'd probably go with something like VOODOO has. That is sweet.


Last question, so you think that even when towing, if I flipped the overloads, I'd still be fine?


Thanks,
Dennis

Dennis,


With airbags, I'd remove the overloads entirely, but flipping negates the need for new U-bolts and the 1" drop. The ride would be better towing and empty, no doubt in my mind. The only argument I can come up with for overloads unmodified is a heavy load all the time ( a camper) and no airbags. Because then you ride all the time on the overload, 100%. But the way it is now, you go from 300 lb/in to over 800 lb/in on contact (each side). on, off, on, off, non-progressive. Don't know why GM put the overload so close to contacting the mains, but i improved it, and wouldn't go back. Lot's of people do it and love it. The unsprung wt is about 2K over the rear axle! That is bucking crazy. Get on a washboard dirt road and don't plan on turning the wheel, the back has a mind of it's own.


I'd say if you have airbags the flip is a no-brainer for wife-comfort, empty, towing whatever, IT"S FREE, the best ride quality improvement for any money.. Even if you lose the airbags, the flipped overloads should still protect the suspension under load to get you home. I chose to flip and dearch them (he did it for free, I can't resist something for free) and moderate bumps still contact the overloads occasionally, keeping in mind I'm down one leaf. I am reminded each time that happens that I can no longer feel expansion joints and highway ride is close to passenger car quality, and vastly improved for a HD pickup truck.


se7enracing


I can't swallow the expense, especially after what I have done, but I have considered it. For the money, it's too experimental for me, and I want to get on to the viair compressor, stainless tank and grover airhorns (which just arrived today). In other words, at $500 per inch, another perspective, I give up.

Michael,


Okay, I'm almost sold on flipping the overloads. I may try it without flipping them first, then flipping them. You are going to love the grovers. I just put on Hadley's and they are awesome! I put mine underneath the passenger side of the inside front of the bed. If you want, I'll take a picture or two and post them. I had a friend make a [free, he did it for free, I can't resist something for free] bent piece of stainless for the horns and another one for the compressor and tank. Mounted the tank and compressor to the frame under the rear passenger door inside the step bar. There were two small holes already in the frame that worked out perfectly.


Thanks again for the info.,
Dennis

What about the cv angles? I cranked my torsion bars about 2 1/2 inches and had a vibration from about 50 to 65 mph? I didnt like the vibration so i lowered front down to stock and it went away??? The 2 1/2 inches is not worth ruining my truck, id rather save the money and get like a 4 inch lift and do it the right way..Also with the torsion bars cranked, and when i had 4wd engaged and took off from a stop it would be very unstable?? So i after all is said and done its back to stock for now....

masterp2, thank you for the detailed post.

what is "flipping the overloads"? Do you mean flipping the springs over and/or removing leafs from the spring pack? if you do that (and have air bags), are things still OK for a heavy tow?

can anyone post pictures of your flipped overloads?

I run timbrens up front and noticed the same charateristics as already mentioned. I have 3/4" of a crank over factory.

JMO but I wouldnt crank over 2" max.

For a firmer ride, has anyone looked into replacing the stock 2500HD torsion bars with the 3500 ones? Not 100% sure, but I thought they were different. What about the snow plow prep package springs...RPO F60?