Any interest in 4wd front coilovers to replace tbars?

[Atomic]

Hey guys, I have been making these for a while but wanted to see if there was any interest on this forum for this sort of thing. Its a bolt on kit that allows you to use aftermarket coilover shocks instead of the factory torsion bars on 4wd gmt800 trucks/suvs.

I did this on my truck (99 silverado) and have about 1000 miles on it and it works great. I have mine set up for drag racing so the CVs are perfectly level, but the same idea will work if you want to go lower or higher. You can get around a 4" drop with the factory spindle and LCA, or a 3-4" lift in front with the factory hardware. And the best part is you have dozens of spring rates and shocks to choose from so you can have your truck ride exactly how you want it. Weight savings is about 40lbs but that wasnt really the point of me making these.

I am at work so I cant post pictures, but they are fully welded 3/8" steel with 1/2" grade 8 hardware and powdercoated flat black. I sell the seperate lower bracket (which you need), and an upper bracket that reinforces the shock hoop (optional). Both together are $315 and either seperate is $180. The whole swap can be done for around $700-800 depending on what parts you use (brands of shocks/springs). I only sell the brackets.

Anyway, let me know if there is any interest and I will post up my full write up. I sell these on a couple other forums, mainly GMFS and performancetrucks.net.

I am new to this forum, but not to others, im a supermod on PT with close to 10k posts, and have almost 7k on FSC and about 1k on gmfs.

Thanks



EDIT:

Edit: I updated my PDFs to include details on the lifted-style upper mounts. This is the same document as before with some additions to include more information.

PDF Explaining the swap: http://www.mediafire.com/view/vkzapsyvtwu5rv9/coilovers_about_v12.pdf
PDF Explaining the installation process: http://www.mediafire.com/view/35n4kssw5cy4ddg/coilovers_install_v12.pdf

Edit1: I added the spreadsheet I made to help with picking out shocks and springs.

 

[Physh1]

I've been following your post over at PT & it's on my list to do first of the year. I'll be contacting you pretty soon for your brackets...

Cameron

 

[digitalfiend]

I saw your thread at PT too a while back. I wondered if it would work on our Tahoe's. Unfortunately, I lost the direct link - would you happen to have it handy?

I love the idea of coilovers in the front, and I love that you've put together a kit to make this easier to do. Based on your description of the kit the price seems very reasonable. Have you done this on enough 2wd or 4wd Tahoes to have an idea of what a good spring rate is for us?

 

[Atomic]

Heres the link to pt: http://www.performancetrucks.net/fo...2/99-07-4wd-front-coilover-conversion-518118/

I was going to see if there was interest for it on this site before I posted basically the same thing over here.

Spring rate depends on what shock you go with, which depends on what ride height you want. Anywhere from 1300 to 650 depending on shock.

 

[digitalfiend]

Heres the link to pt: http://www.performancetrucks.net/fo...2/99-07-4wd-front-coilover-conversion-518118/

I was going to see if there was interest for it on this site before I posted basically the same thing over here.

Now THAT is trick. And you have limiting straps engineered in - I love it. I need mounts for limiting straps in the rear of my Tahoe right now, but that's for another thread. I hadn't seen the pictures before, thank you for the direct link.

It's a bummer that you have to trim the bump stops...keeps one from easily reverting if they are so inclined in case they sell their ride. After I installed QA1's on the rear of my Tahoe I'm of the Charlton Heston mindset: you can have my QA1's WHEN YOU PRY THEM FROM MY COLD DEAD HANDS!!! In all seriousness, I guess you could always swap out any basic coilover shock with the right spring rate.

Spring rate depends on what shock you go with, which depends on what ride height you want. Anywhere from 1300 to 650 depending on shock.

That spring rate range is quite a bit, but it's a good ballpark to start with. Do you happen to know the spring rate of the 2WD and 4WD Tahoe torsion bars is?

 

[Atomic]

I actually dont use straps anymore because ive found I dont need them, but they can be easily added.

Yea the bumpstops do need to be trimmed, but only the corner area, it actually doesnt change having the stock bumpstop there. I highly recommend adding in aftermarket one on the bottom instead of on top like the factory one. You can easily put the torsion bars back on just now the bumpstop is on the bottom instead of the top, no big deal.

Torsion bars would have a stiffness per angle since they are being twisted not compressed like a coil spring, and also the geometry is a little different so the numbers arent really directly comparable. On my truck, which has about 1450lb over each front wheel, 900lb is close to the factory torsion bars.

 

[Bomba02]

Think i just found my next suspension mod. Looks killer man, must change the ride a ton with more adjustment spring rate to pick from.
So if i did the coil over conversion i could ditch doing the djm lca drop and lower it with the coil over set up? I had plans in the future to do the djm lca arms and reinstall stock keys for a better ride up front. Instead id go this route all day, your brackets look killer and top notch! Would this work with drop spindles? Do you have any info on spring rates for the suv's being heavier then the pickup's? i have the 6.0 in my nali prob be a little heavier? sorry for the all question just very interested in doing this in the future. If i had the money id jump on it now. Thanks for any info man, your conversion looks great!
Billy

 

[Atomic]

Thanks man. Yea it uses the stock LCA. I have not tried different spindles but I suspect you cant use an aftermarket one because of the required shock distance. I am not positive though...

the SUVs weigh around 6000lb I think, so around 1500-1600 per corner. It depends on what shock you use, but if you use the QA1 DS301 with a stud top (which would give you the most possible drop, ie, lowest ride height) you would want a 1200-1300lb spring. As the travel of the shock gets longer you dont need as stiff of a spring. I have only used QA1 shocks on mine, so I cant comment on other shock brands.

 

[YukonXL04]

question... Will this not work on 2wd yukons?

 

[digitalfiend]

I actually dont use straps anymore because ive found I dont need them, but they can be easily added.

Yea the bumpstops do need to be trimmed, but only the corner area, it actually doesnt change having the stock bumpstop there. I highly recommend adding in aftermarket one on the bottom instead of on top like the factory one. You can easily put the torsion bars back on just now the bumpstop is on the bottom instead of the top, no big deal.

I'm running really low on the front of my Tahoe...changing the bump stops has occurred to me in order to get more travel, so this is very attractive to me. Changing to coilovers allows one to get away from the torsion+jounce stops that can be troublesome. The more I think about it, the more your kit has SEXY written all over it.

Torsion bars would have a stiffness per angle since they are being twisted not compressed like a coil spring, and also the geometry is a little different so the numbers arent really directly comparable. On my truck, which has about 1450lb over each front wheel, 900lb is close to the factory torsion bars.

I see your point about the stiffness per angle. I just put new QA1 shocks on the rear of my Tahoe but the front still needs new shocks (preferably matching QA1's). I'm holding off due to my Tahoe budget being dry for the time being...but I'm also holding off to see someone with an SUV do this who has 2" drop spindles and can test the waters with regard to spring rate for the coil-over.

Do you make these kits to order, or do you make a batch of them at a time?

 

[Atomic]

question... Will this not work on 2wd yukons?

I was under the impression the 2wd tahoes have coil springs up front, in which case, no. My kit uses the LCA that has factory torsion bars. This doesnt mean you cant put coilovers on your truck, it just means you may not need my lower bracket. I believe my upper brackets can be used in 2wd applications if you find a means of mounting the bottom of the coilover to something.

I'm running really low on the front of my Tahoe...changing the bump stops has occurred to me in order to get more travel, so this is very attractive to me. Changing to coilovers allows one to get away from the torsion+jounce stops that can be troublesome. The more I think about it, the more your kit has SEXY written all over it.


I see your point about the stiffness per angle. I just put new QA1 shocks on the rear of my Tahoe but the front still needs new shocks (preferably matching QA1's). I'm holding off due to my Tahoe budget being dry for the time being...but I'm also holding off to see someone with an SUV do this who has 2" drop spindles and can test the waters with regard to spring rate for the coil-over.

Do you make these kits to order, or do you make a batch of them at a time?

I have sold a couple sets to tahoe guys but I am still waiting on feedback, not sure if they have got around to installing them yet.

Torsion bars are meant to be used with the factory jounce bumpers, without them you would be all over the place. In a coilover setup, they are really just there to limit downtravel and prevent damage to the shock.

Spring rate is going to depend on how stiff or how soft you want the ride, and also what length shock which depends on what ride height you want. So you see there isnt really a one size fits all, its tailored to what you want. With that said, in a slightly lowered setup, 1000-1300 would be the range I expect most want to be in.

I just made a batch of about 9 bottom sets and 10 top sets a couple weeks ago along with all the hardware. I have these sitting on my workbench at home ready to go.

 

[Bomba02]

Thanks man. Yea it uses the stock LCA. I have not tried different spindles but I suspect you cant use an aftermarket one because of the required shock distance. I am not positive though...so your not sure if I can i use the drop spindles, I'd would just have to order the correct length coil over shock maybe to fit. Interesting.

the SUVs weigh around 6000lb I think, so around 1500-1600 per corner. It depends on what shock you use, but if you use the QA1 DS301 with a stud top (which would give you the most possible drop, ie, lowest ride height) you would want a 1200-1300lb spring. As the travel of the shock gets longer you dont need as stiff of a spring. I have only used QA1 shocks on mine, so I cant comment on other shock brands.

thanks for all the info man .so your not sure if I can i use the drop spindles, Would I just have to order the correct length coil over shock maybe to fit. Interesting. I'm really wanting this mod. Haha. Hopefully you have some available when I'm ready to purchase. Some info from guys that have this done to there hoes/yuk would be perfect.
Billy

 

[bottomline2000]

I've been looking at this mod on PT.net also and the big question is shock setup. going lowered is the plan and this lets you keep all stock arms. i would prefer to just flip the UCA with this mod to get a 3-4" drop in the front. I want to see more info on shock/spring setup to see what works. I want a stiffer ride like the bilsteins I have now. just no idea how to make it happen lol. real cool mod though.

 

[livingez_123]

Not a bad idea, but with only 2.5" inches of travel I don't think it would be ideal for a DD. people like these trucks/SUV's because they ride nice, and they have suspension to soak up the roads in this once great nation. Air would be a smoother way to go. JMHO
Have you found any issues with the upper shock mount being able to handle the extra weight? Do you have any kits out there that have 30-50k on them yet?

 

[YukonXL04]

I was under the impression the 2wd tahoes have coil springs up front, in which case, no. My kit uses the LCA that has factory torsion bars. This doesnt mean you cant put coilovers on your truck, it just means you may not need my lower bracket. I believe my upper brackets can be used in 2wd applications if you find a means of mounting the bottom of the coilover to something..

I don't know about the rest of these Tahoe's, but my Yukon XL has the torsion bar setup. No coil springs up front. I didn't know any of the GM trucks came with coils up front. But my 00 Sierra was a 2500 4x4 so I just assumed they all had torsion bars.

 

[Atomic]

I've been looking at this mod on PT.net also and the big question is shock setup. going lowered is the plan and this lets you keep all stock arms. i would prefer to just flip the UCA with this mod to get a 3-4" drop in the front. I want to see more info on shock/spring setup to see what works. I want a stiffer ride like the bilsteins I have now. just no idea how to make it happen lol. real cool mod though.

I have never messed with flipping the UCA so I cant really help you there, but the math is pretty straightforward to figure out what spring and shock you need, or at least the specs of each. With adjustable shocks like the ones i use, qa1 ds301, you can adjust it from extra squishy to riding like a wagon.

Not a bad idea, but with only 2.5" inches of travel I don't think it would be ideal for a DD. people like these trucks/SUV's because they ride nice, and they have suspension to soak up the roads in this once great nation. Air would be a smoother way to go. JMHO
Have you found any issues with the upper shock mount being able to handle the extra weight? Do you have any kits out there that have 30-50k on them yet?

The travel really isnt that big of a deal when you consider the stock setups only have about 4" and most of that is taken up when its sitting on the jounce bumper. Like I said above, you can adjust shock settings with an adjustable shock to whatever dampening setting you want, extra squishy to really firm with just a knob. I like my ride stiff and I have mine set at 12/18 so plenty more to go. This ride a whole lot better than the torsion bars I had.

The upper brackets I made help support the load on the frame so your not just on the shock hoop. They are 3/8" steel fully welded...if someone breaks one I would give them a medal

I have the original kit and probably have 1200 miles on them. The only issue I had was the plastic bearings giving up very early. After I replaced them with steel ones I have not had a single issue. I just came out with these this summer, so 30-50k miles would be impressive.

I don't know about the rest of these Tahoe's, but my Yukon XL has the torsion bar setup. No coil springs up front. I didn't know any of the GM trucks came with coils up front. But my 00 Sierra was a 2500 4x4 so I just assumed they all had torsion bars.

I know the newer ones do, but I thought the gmt800 2wd tahoes did as well...could be wrong. All 2500 trucks still use torsion bars I think.

But to answer your question, regardless of 2wd or 4wd, if you currently have a torsion bar setup these should work for you.

 

[Tahoewhat]

This is a great thread. I have thought about coil overs, but never looked into it, or goggled it should i say in today's world. But will be reading up more on the benefits of this over Tbar set up. My tahoe is pretty low and could use improvement and adjust-ability would be a nice thought.

What about the rear?

 

[Bomba02]

This is all of been thinking of lol. The ride would be way better then T bars when lowered. Atomic mentioned that it might not work with drop spindles? I have drop spindles and would want to keep them and do the coil over conversion instead of the djm lca to obtain more drop and better ride. I need to find more info or insight to this. Like stated the ride and adjustability would be great. One other thing is its my DD as well would need to be able to handles miles roads but it looks/sounds like it would.

Tahoewhat I thought about the rear as well. Could they just be put in place of the factory shocks or would they need to be mounted differently? This could be the way to lower rear more just set alex at your deserved ride height measure and figure out which coil overs lengths would be needed. I'm on Tony's 6 inches springs so unless I bag the rear I'm as low as I can go.....Going coil over would let me lower it more which I'd rather do this then bags.
Billy.

 

[livingez_123]

I don't see why it wouldn't work with the drop spindles, his kit mounts to the lca. the uca and lca remain the same distance apart with the drop spindles as with the stock. the big difference is the hub is moved up 2". if its a 2wd then there is no axle to get in the way, 4wd maybe, but just measure it to be sure.

look to see how much room you have now between you axle and stock shock, if you have 1" or less it might be real close. more than an inch I would think your good to go. Your centering the coil over where the stock shock is now. The stock shock has a OD of about 2". the springs are about 4" in OD. this will give you an idea of how close you can get. but make sure you check with the wheels in all directions.

 

[Tahoewhat]

This is all of been thinking of lol. The ride would be way better then T bars when lowered. Atomic mentioned that it might not work with drop spindles? I have drop spindles and would want to keep them and do the coil over conversion instead of the djm lca to obtain more drop and better ride. I need to find more info or insight to this. Like stated the ride and adjustability would be great. One other thing is its my DD as well would need to be able to handles miles roads but it looks/sounds like it would.

I don't see why it wouldn't work with the drop spindles, his kit mounts to the lca. the uca and lca remain the same distance apart with the drop spindles as with the stock. the big difference is the hub is moved up 2". if its a 2wd then there is no axle to get in the way, 4wd maybe, but just measure it to be sure.

Lol. It is kind of all i thought of today till something happened. But the idea sounds great. Just needs more research on my end and some feedback from people that have done this. Not to sound like an a$$, but how do you know the ride would be better? Asking b/c i honestly do not know. So please dont take that as a mean way. Tbar is the oddest setup i have seen and still dont get it. lol. Dont know how are bar does the front suspension on these heavy trucks and tahoes, etc.

I have drop spindles as well, and even if this does not work w/ them, which i agree w/ living, i dont see why they would not work. the brackets dont do anything w/ the spindles. Like stated, 4wd might be a problem or awd and spindles. From what i have seen and skimmed over.

ah.. and my tahoe is my DD as well. So ride is kind of a big thing and cant really experiment if this does not work out right.

Be the guinnea pig. lol

Tahoewhat I thought about the rear as well. Could they just be put in place of the factory shocks or would they need to be mounted differently? This could be the way to lower rear more just set alex at your deserved ride height measure and figure out which coil overs lengths would be needed. I'm on Tony's 6 inches springs so unless I bag the rear I'm as low as I can go.....Going coil over would let me lower it more which I'd rather do this then bags.
Billy.

I do not know if you could put them where the shocks go. The springs go in the pocket and the shocks on the outter side. (yall know what i mean) So i dont know. Not sure i would want the weight of my tahoe sitting where the shocks go by themselves. Especially right now on shock relocators. Will add this to my research. lol

look to see how much room you have now between you axle and stock shock, if you have 1" or less it might be real close. more than an inch I would think your good to go. Your centering the coil over where the stock shock is now. The stock shock has a OD of about 2". the springs are about 4" in OD. this will give you an idea of how close you can get. but make sure you check with the wheels in all directions.

Maybe i messed up these quotes, but what do you mean measure the shock and axle distance? Or is this for the front setup?

Either way. Im really liking this idea if i could go back to stock spindles (get my turning back) and then slam it back down and ride better.