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Posted

Hello,

 

So I am kind of in a pickle. I currently have a 2020 GMC Sierra SLT X31 with the upgraded 2" GM suspension, so essentially made it an AT4 in regards to the suspension. The suspension is great, however, the rake is is about 2 inches difference and I was wanting to level out the front. I read that by leveling out this lift I am essentially turning it into a 4" lift without differential drop brackets, causing extreme angles on the CV shafts leading to premature wear and not allowing the use of 4WD AUTO without risking serious damage.

 

I was looking at the BDS 2.5" lift for AT4/TB since my suspension components are now like that of an AT4. This kit comes with drop brackets and would make my lift essentially a 4.5" lift all around, which is what I want! The issue is that specific lift is only sold as a coilover kit and they are asking for 4K. Understand it is a great kit, but a little much for the gain of "leveling" out my front by 2.5"

 

My ultimate question is this. I still have all the components from the original suspension (prior to the 2" upgrade) and was wondering if I went ahead and purchased the 4" BDS for  for the regular (non AT4/TB) Sierra that I originally had, would I just need to bring the original shorter CV shafts to swap out from the longer ones that I have now from the 2" upgrade? The BDS 4" non-coilover kit is 2k and this approach would essentially save me 2k. Worth it, going this route?

 

Thank you

Posted
50 minutes ago, lapoolboy said:

Keep the longer axles in place.

I must be missing something then. So are the 4" non coilover lift kits that BDS offers, the same for both the "AT4" and "Regular?" There is a ~$70 difference in the 2.

 

If so does the costumer gets to choose then whether they want to "stack" the 4" lift and turn and AT4 into a 6" lift or remove all the 2" lift components and just make it a 4" lift?

Posted (edited)

For AT4 - (your current equal) - the BDS 2.5" lift - is equal to a 4" lift on regular truck.  The BDS 4" lift for AT4/TB - is a 6" lift on regular truck.

 

I have AT4 with 2.5" coilover kit - it was expensive - but the upgraded shocks improve the overall ride and make the truck very offroad capable.  If you have the budget you will not regret making the change.  I had a 2019 AT4 with Ready Lift 2" SST level kit - the BDS set up is night and day better than that set up.

 

Below is a photo of my truck wiht 2.5" BDS - you will see it still has some rake - if you want none you could leave out the BDS blocks and stick with the 2" blocks that came with 2" lift kit from GM you have on now, however it will be about 1/2" nose high. 

 

If you do just want to level with no shocks then Zone is a great option for you - Zone is owned by BDS - it is a similar kit with both made in the same warehouse and coilover shocks are "not" required - they offer a 4" lift for stock height - so 4" overall or a 4" to your current AT4 height - so 6" overall.   Costs far less and does not require expensive Fox shocks.    Links for those below: 

 

Zone 4" (4" over AT4 so 6: lift ) link:  https://zoneoffroad.com/products/4-in-ifs-suspension-lift-kit-2019-2020-chevy-trail-boss-gmc-at4?variant=33699132702808

 

If you want to go back to "stock height" Zone also offers a 4" lift kit from stock height.  Again - no shock purchase is required.   

 

Zone 4" (4" over stock, so 4: lift) -  link: https://zoneoffroad.com/products/4-in-suspension-lift-kit?variant=33699132670040 

 

 

1767178234_TruckFox2.thumb.JPG.c7935ae8998a5481cfcd49aa771ce791.JPGIMG_9550.thumb.JPG.1616557079f989c6d155e02b3dd61464.JPG

 

1765863746_BDS2.thumb.JPG.02ba8582dfbc333c085b5100bb7341d2.JPG

Edited by Supercup
  • Like 3
Posted

Agree with Supercup on this one. The BDS 2.5" on my AT4 is a great upgrade from the OEM Ranchos. I don't do any off road but on road is amazing!

 

Jim

  • Like 1
Posted (edited)

i would think you could keep longer CV axles and do a 1" drop on differential and be fine.......moreso than the length is the angle, you want them as flat as can be or at least stock angles....think GM made them longer cuz they left differential height unchanged

 

BDS makes great kits, the ride and longevity of real kit are well worth cost..

 

baja kits has one with LCA that is nice (think its 4" total in front).....lower arm adds the lift in combo with adj coilover.....KING 3.0 shocks are an option....fox has 3.0 as well i believe

 

size of the piston and diameter of the shaft make all the difference.....just has more capacity to do same job with less stress/heat....drove a truck that had bypass 3.0 KINGs and was shocked how smooth it was on highway

 

 

Edited by Dunn
Posted (edited)
3 hours ago, Supercup said:

For AT4 - (your current equal) - the BDS 2.5" lift - is equal to a 4" lift on regular truck.  The BDS 4" lift for AT4/TB - is a 6" lift on regular truck.

 

I have AT4 with 2.5" coilover kit - it was expensive - but the upgraded shocks improve the overall ride and make the truck very offroad capable.  If you have the budget you will not regret making the change.  I had a 2019 AT4 with Ready Lift 2" SST level kit - the BDS set up is night and day better than that set up.

 

Below is a photo of my truck wiht 2.5" BDS - you will see it still has some rake - if you want none you could leave out the BDS blocks and stick with the 2" blocks that came with 2" lift kit from GM you have on now, however it will be about 1/2" nose high. 

 

If you do just want to level with no shocks then Zone is a great option for you - Zone is owned by BDS - it is a similar kit with both made in the same warehouse and coilover shocks are "not" required - they offer a 4" lift for stock height - so 4" overall or a 4" to your current AT4 height - so 6" overall.   Costs far less and does not require expensive Fox shocks.    Links for those below: 

 

Zone 4" (4" over AT4 so 6: lift ) link:  https://zoneoffroad.com/products/4-in-ifs-suspension-lift-kit-2019-2020-chevy-trail-boss-gmc-at4?variant=33699132702808

 

If you want to go back to "stock height" Zone also offers a 4" lift kit from stock height.  Again - no shock purchase is required.   

 

Zone 4" (4" over stock, so 4: lift) -  link: https://zoneoffroad.com/products/4-in-suspension-lift-kit?variant=33699132670040 

 

 

1767178234_TruckFox2.thumb.JPG.c7935ae8998a5481cfcd49aa771ce791.JPGIMG_9550.thumb.JPG.1616557079f989c6d155e02b3dd61464.JPG

 

1765863746_BDS2.thumb.JPG.02ba8582dfbc333c085b5100bb7341d2.JPG

very nice man!

 

thats the way to go, no issues, worries and truck drives and handles beautiful....

 

your CVs look perfect

Edited by Dunn
Posted (edited)

 

13 hours ago, Supercup said:

For AT4 - (your current equal) - the BDS 2.5" lift - is equal to a 4" lift on regular truck.  The BDS 4" lift for AT4/TB - is a 6" lift on regular truck.

 

I have AT4 with 2.5" coilover kit - it was expensive - but the upgraded shocks improve the overall ride and make the truck very offroad capable.  If you have the budget you will not regret making the change.  I had a 2019 AT4 with Ready Lift 2" SST level kit - the BDS set up is night and day better than that set up.

 

Below is a photo of my truck wiht 2.5" BDS - you will see it still has some rake - if you want none you could leave out the BDS blocks and stick with the 2" blocks that came with 2" lift kit from GM you have on now, however it will be about 1/2" nose high. 

 

If you do just want to level with no shocks then Zone is a great option for you - Zone is owned by BDS - it is a similar kit with both made in the same warehouse and coilover shocks are "not" required - they offer a 4" lift for stock height - so 4" overall or a 4" to your current AT4 height - so 6" overall.   Costs far less and does not require expensive Fox shocks.    Links for those below: 

 

Zone 4" (4" over AT4 so 6: lift ) link:  https://zoneoffroad.com/products/4-in-ifs-suspension-lift-kit-2019-2020-chevy-trail-boss-gmc-at4?variant=33699132702808

 

If you want to go back to "stock height" Zone also offers a 4" lift kit from stock height.  Again - no shock purchase is required.   

 

Zone 4" (4" over stock, so 4: lift) -  link: https://zoneoffroad.com/products/4-in-suspension-lift-kit?variant=33699132670040 

 

 

 

 

 

 

Thanks for all the info, that was very helpful! Your truck/set up looks great man, and I would be ok with a slight rake such as yours!

 

Quick question tho, in regards to the 4" (non coilover) Zone lift kit over stock (making it a 4" all around). When comparing the same style lift, would it be better to just go with the BDS'  4" lift over "stock?"

 

BDS 4" non-coilover -  https://bds-suspension.com/product?ma=5&mo=1&ty=114&yr=2019-2021

 

 

Edited by Kdembo03
Posted
10 hours ago, Dunn said:

i would think you could keep longer CV axles and do a 1" drop on differential and be fine.......moreso than the length is the angle, you want them as flat as can be or at least stock angles....think GM made them longer cuz they left differential height unchanged

 

BDS makes great kits, the ride and longevity of real kit are well worth cost..

 

baja kits has one with LCA that is nice (think its 4" total in front).....lower arm adds the lift in combo with adj coilover.....KING 3.0 shocks are an option....fox has 3.0 as well i believe

 

size of the piston and diameter of the shaft make all the difference.....just has more capacity to do same job with less stress/heat....drove a truck that had bypass 3.0 KINGs and was shocked how smooth it was on highway

 

 

Awesome, thanks for the info!

 

And yes, Gm made them longer because their lift does not have differential drop brackets. That it why I was wondering if I took it back to the original stock height (no 2" lift") would they then be too long, because the non AT4/TB lifts account for the shorter CV axle with their drop brackets, and now I would essentially have longer ones.

 

I am thinking I will be just fine with 1" drop differential though like you stated. I may just go with the 2.5" BDS coilover that goes with my current 2" lift anyhow and improve the ride!

Posted
On 2/5/2021 at 4:47 AM, Kdembo03 said:

 

 

Thanks for all the info, that was very helpful! Your truck/set up looks great man, and I would be ok with a slight rake such as yours!

 

Quick question tho, in regards to the 4" (non coilover) Zone lift kit over stock (making it a 4" all around). When comparing the same style lift, would it be better to just go with the BDS'  4" lift over "stock?"

 

BDS 4" non-coilover -  https://bds-suspension.com/product?ma=5&mo=1&ty=114&yr=2019-2021

 

 

 

I would print out the BDS and Zone kits list of whats included side by side and then see if the BDS price premium is worth the difference.  BDS offers a lifetime warranty - but you are unlikely to ever need that.   Both offer great options. 

Posted
On 2/8/2021 at 12:14 PM, Supercup said:

 

I would print out the BDS and Zone kits list of whats included side by side and then see if the BDS price premium is worth the difference.  BDS offers a lifetime warranty - but you are unlikely to ever need that.   Both offer great options. 

Thank you!

 

So I spoke with BDS and they told me that the longer CV shafts that are on my truck now would require a kit made strictly for AT4/TB. Sounds like I would have to replace my current longer ones with the previous shorter ones if I want to run the zone kit or BDS non-AT4/TB kits.

 

The 2.5" coilover that BDS offers is starting to look better and better lol.

  • Like 1
Posted
8 hours ago, Kdembo03 said:

I spoke with BDS and they told me that the longer CV shafts that are on my truck now would require a kit made strictly for AT4/TB.

You got an ignorant rep.

 

  • Like 1
Posted

yeah cant see them being that big a deal.....if your raising it 2.5 and only using a 1" diff drop thats still 1.5" over stock.....and TB is 2"...

if you go even higher and still use 1" diff drop longer CVs would be even better....

 

 

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