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Discussion Starter #1
The 03 2500HD has 5100 Bilsteins and is leveled with Cognito keys. I’m running 285/70-17’s. Everything else is stock. I understand that a 2500HD truck isn’t going to ride like a luxury sedan. But, would like to invest to get it as comfortable and smooth as possible both without load and with load (I tow a fully loaded 24’ Toyhauler).

I’ve read that installing bags in the rear helps under load. Do the Sulastic Shackles help (with or without load)? What else should I do? If needed, I would also consider removing the cognito keys. Your help is greatly appreciated.
 

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Saying that your truck is leveled, I want to see the front end geometry to see how bad your angles are. That will tell a lot, and I would guess that your front end it cranked up too high and contributing to your harsh ride. Realistically it shouldn't need turned up a whole lot to clear 285/17s but I also realize that each truck has its own quirks and whatnot. I have 305/65/17s on my 2002 and have no rubbing at ride height and with the front end fully dropped for sled pulling. So, lets see what your angles look like and we can go from there
 

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Discussion Starter #5
Saying that your truck is leveled, I want to see the front end geometry to see how bad your angles are. That will tell a lot, and I would guess that your front end it cranked up too high and contributing to your harsh ride. Realistically it shouldn't need turned up a whole lot to clear 285/17s but I also realize that each truck has its own quirks and whatnot. I have 305/65/17s on my 2002 and have no rubbing at ride height and with the front end fully dropped for sled pulling. So, lets see what your angles look like and we can go from there
Thanks for helping. Not exactly sure what pics work best to help see this so here's a few to start. I can take more if needed. Please just tell me what else you need to see.
 

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Discussion Starter #6
Just FYI....the pics are as follows - Full View side of truck, Side View of Front Passenger Wheel Well, Front Passenger Suspension Front View, Front Passenger Suspension Rear View
 

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Now this is me-some people will disagree, some will probably jump me, some will agree. I've had my 02 cranked way high, cranked up just a little, not cranked at all (cv angles parallel with ground), and lowered. I am going to tell you your front end is too high and that's where your harsh ride is coming from. Your cv angles aren't the most extreme I've seen, but they aren't great.

The torsion bars raise the truck the more they are twisted. As you raise the truck, you basically twist the bar harder to overcome the weight more. As you do this, you also lose the give of the 'spring' to absorb the bumps and imperfections of the road. If you lower the front down, and make the cv's and control arms more parallel with the ground instead of angling down, it will give the torsion bar more ability to absorb and dampen the bumps. Yes, the shocks absorb the impacts, but if the torsion bar 'spring' is too stiff to give, then the shocks can't do much.

The rear is going to be kinda stiff with no load, but its not horrible. The airbags are made to help support the load if you have too much squat when the weight of the toyhauler is on. I've not personally used the sulastic shackles, but have heard positive about them-several on here.

Like I said, there are people who will agree with my words, and there are people who will disagree. And part of what we can't tell is if the harshness you are talking about is from the front or the rear. But coming from a guy who has had seven different classic-body trucks on all levels except completely slammed on the ground all the way around, that is what advice I can give you
 

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Discussion Starter #8
Now this is me-some people will disagree, some will probably jump me, some will agree. I've had my 02 cranked way high, cranked up just a little, not cranked at all (cv angles parallel with ground), and lowered. I am going to tell you your front end is too high and that's where your harsh ride is coming from. Your cv angles aren't the most extreme I've seen, but they aren't great.

The torsion bars raise the truck the more they are twisted. As you raise the truck, you basically twist the bar harder to overcome the weight more. As you do this, you also lose the give of the 'spring' to absorb the bumps and imperfections of the road. If you lower the front down, and make the cv's and control arms more parallel with the ground instead of angling down, it will give the torsion bar more ability to absorb and dampen the bumps. Yes, the shocks absorb the impacts, but if the torsion bar 'spring' is too stiff to give, then the shocks can't do much.

The rear is going to be kinda stiff with no load, but its not horrible. The airbags are made to help support the load if you have too much squat when the weight of the toyhauler is on. I've not personally used the sulastic shackles, but have heard positive about them-several on here.

Like I said, there are people who will agree with my words, and there are people who will disagree. And part of what we can't tell is if the harshness you are talking about is from the front or the rear. But coming from a guy who has had seven different classic-body trucks on all levels except completely slammed on the ground all the way around, that is what advice I can give you
Thanks for the quick and insightful suggestions/recommendations. Just out of curiosity, if I replaced the UCA's with Cognito UCA's would that help or will is it still recommended to adjust the torsion bars regardless? I would prefer not to lose the level it currently has but if lowering the front is the only way to dramatically improve the ride, then that's what I'll do.
 

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Thanks for the quick and insightful suggestions/recommendations. Just out of curiosity, if I replaced the UCA's with Cognito UCA's would that help or will is it still recommended to adjust the torsion bars regardless? I would prefer not to lose the level it currently has but if lowering the front is the only way to dramatically improve the ride, then that's what I'll do.
That in itself will not improve the ride quality. I have them on my 02, what they do more than help the ride is help correct geometry issues when the front is cranked a lot like yours. Yes, it can help some because with their design you can bolt the ball joint in on top of the control arm or below the control arm. If you bolt them in below, it helps raise the front of the truck, and you could then potentially lower the torsion bars down some and keep your current ride height. So I guess its kind of a yes-and-no-possibly kind of answer.

I swapped to the Cognito UCAs for a couple different reasons. I was doing a complete front end rebuild, they have a separate serviceable ball joint that is easily replaceable, and it helps correct alignment issues. But also when I did this rebuild, when everything came back together, I set the front end lower than before the rebuild. I went from cranked really high to being just a touch above having the cv axles parallel with the ground.
 

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Discussion Starter #10
That in itself will not improve the ride quality. I have them on my 02, what they do more than help the ride is help correct geometry issues when the front is cranked a lot like yours. Yes, it can help some because with their design you can bolt the ball joint in on top of the control arm or below the control arm. If you bolt them in below, it helps raise the front of the truck, and you could then potentially lower the torsion bars down some and keep your current ride height. So I guess its kind of a yes-and-no-possibly kind of answer.

I swapped to the Cognito UCAs for a couple different reasons. I was doing a complete front end rebuild, they have a separate serviceable ball joint that is easily replaceable, and it helps correct alignment issues. But also when I did this rebuild, when everything came back together, I set the front end lower than before the rebuild. I went from cranked really high to being just a touch above having the cv axles parallel with the ground.
This is extremely helpful. Thanks so much. I may try swapping the Cognito UCA's, bolt the ball joint below the control arm and then adjust the torsion bars accordingly to get the cv axles as parallel to the ground as possible. Based upon what you mentioned, this may still give me some leveling but also should correctly align the CV axles to give a much better ride. Let me know if I misunderstood.
 

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This is extremely helpful. Thanks so much. I may try swapping the Cognito UCA's, bolt the ball joint below the control arm and then adjust the torsion bars accordingly to get the cv axles as parallel to the ground as possible. Based upon what you mentioned, this may still give me some leveling but also should correctly align the CV axles to give a much better ride. Let me know if I misunderstood.
It will likely help, but probably not get the angles down to being level. But, it could be enough of a change to make it satisfactory to your comfort level. And remember, any time ball joints or control arms are changed-get an alignment. If you adjust the torsion bars it will affect the alignment. So, if you swap to the Cognito arms, move the truck around a bit, get your torsion bars adjusted to where you are satisfied, and then get an alignment to avoid wearing the tires.
 

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Discussion Starter #12
So, if you swap to the Cognito arms, move the truck around a bit, get your torsion bars adjusted to where you are satisfied, and then get an alignment to avoid wearing the tires.
Definitely. Fortunately, I have a lifetime alignment contract with Firestone so getting an alignment costs nothing but time at this point.
 

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I'll second what DMAXFF is stating...and just from my personal background, my previous truck was an '04 LLY that I ran leveled not long after I purchased it new, until I sold it in early 2016 to get what I have now. I also towed a 24' toyhauler very frequently. My torsions were cranked to just slightly below level. I ran 285's also, but I trimmed the lower plastic under the front bumper at about a 30 degree or so angle for a little more clearance. From your pics, you seem to be a little higher in the front with room to lower it down a little. This will definitely improve the ride. Mine was a little stiffer than it was stock, but only more "truck" like. Not harsh at all. My CV angles were increased a little, but still much flatter than yours. The ribs of your CV boots appear to be touching which is something we that should be avoided as much as possible. In the 12 years I had the '04 and put on over 160,000 miles leveled, I never had any serious front end issues. Now I did have to replace the ball joints a few times, and if my memory is correct, I did replace the idler and pitman arms a couple times, but that was really it...aside from routine alignments and normal tire replacements / rotations. And I ran the stock UCAs. If we choose to level, lift, or lower, we are altering the stock geometry. This will have an effect on the components and will likely increase the wear, thus requiring an increased replacement frequency.
 

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I'll second what DMAXFF is stating...and just from my personal background, my previous truck was an '04 LLY that I ran leveled not long after I purchased it new, until I sold it in early 2016 to get what I have now. I also towed a 24' toyhauler very frequently. My torsions were cranked to just slightly below level. I ran 285's also, but I trimmed the lower plastic under the front bumper at about a 30 degree or so angle for a little more clearance. From your pics, you seem to be a little higher in the front with room to lower it down a little. This will definitely improve the ride. Mine was a little stiffer than it was stock, but only more "truck" like. Not harsh at all. My CV angles were increased a little, but still much flatter than yours. The ribs of your CV boots appear to be touching which is something we that should be avoided as much as possible. In the 12 years I had the '04 and put on over 160,000 miles leveled, I never had any serious front end issues. Now I did have to replace the ball joints a few times, and if my memory is correct, I did replace the idler and pitman arms a couple times, but that was really it...aside from routine alignments and normal tire replacements / rotations. And I ran the stock UCAs. If we choose to level, lift, or lower, we are altering the stock geometry. This will have an effect on the components and will likely increase the wear, thus requiring an increased replacement frequency.
Thanks, I appreciate your feedback. I’m exactly leveled front and back but will start with lowering the front since it doesn’t cost me anything except maybe an alignment. If that improves the ride, then I may upgrade and replace the UCA’s and then adjust again to maintain the geometry and still keep a better ride. Thanks
 

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I don't think I see the jounce bumpers in your front suspension. Perhaps not looking in the correct place. If yours are gone, NOT having them can cause a rough ride. Although my truck is a 2WD, I found that one of mine was torn, ineffective, and replacing it made for a substantially better drive. Your 4WD truck appears to have been made with this part. In any case, check the part itself to make sure it is not torn nor damaged. Only 1 bolt to remove it.



GM Part No.: 15835666

Bumper,Front Lower Control Arm
About $28
 

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Discussion Starter #16
I don't think I see the jounce bumpers in your front suspension. Perhaps not looking in the correct place. If yours are gone, NOT having them can cause a rough ride. Although my truck is a 2WD, I found that one of mine was torn, ineffective, and replacing it made for a substantially better drive. Your 4WD truck appears to have been made with this part. In any case, check the part itself to make sure it is not torn nor damaged. Only 1 bolt to remove it.



GM Part No.: 15835666

Bumper,Front Lower Control Arm
About $28
Thanks, you’re right. I checked and it’s obliterated in the driver’s side too so ordered two. Thanks
 

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Discussion Starter #17
Installed the jounce bumpers and lowered the front 1 inch (10 turns). Do the angles look better? The ribs of the CV boots aren't touching anymore. Seems to ride a bit better but could just be psychological. The true test is to have my wife and daughter ride in it.
 

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Installed the jounce bumpers and lowered the front 1 inch (10 turns). Do the angles look better? The ribs of the CV boots aren't touching anymore. Seems to ride a bit better but could just be psychological. The true test is to have my wife and daughter ride in it.
It’s actually 5 full turns (10 half turns)
 

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Installed the jounce bumpers and lowered the front 1 inch (10 turns). Do the angles look better? The ribs of the CV boots aren't touching anymore. Seems to ride a bit better but could just be psychological. The true test is to have my wife and daughter ride in it.
Angles do look better, so I would run with that for a couple weeks and see how you like it. Ultimately that's an answer only you can come to, since its your truck and your comfort level. Between the lower tension on the torsion bar and the jounce bumper being in place now, its bound to make some difference.

I thought about the jounce bumper when I looked at your picture, but in my truck that didn't seem to matter much-but I'm a lot lower than you are as well
 

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The GM front suspension was designed so that the LCAs are resting on, or at least touching the jounce bumpers. They are an integral part of the suspension and if they're not adjusted right the truck will ride poorly.
 
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