Factory Spring Part Numbers & Associated Lift

by **boog2006** » Wed Apr 04, 2012 10:51 pm

I ordered the moog 81114's.

Lift should be here tomorrow so hopefully I'll get them installed soon. I'll definitely post up

by **hobbstisdaman** » Wed Apr 11, 2012 9:22 pm

So I found my front springs were 6ac and 7ac. When I looked up those (since they weren't on the list on here) It gave me Front chassis spring 15058529. Which apparently "computer tuned." Does this mean anything extravagant besides me having to figure out the spring rate on my own?

by **Dirtyd** » Thu Apr 12, 2012 12:09 am

Okay I'm not going to lie, I just read through this whole thread and its like trying to learn a different language.

What front springs can I still buy for a stiffer ride and for the HD Bilsteins.

by **The Roadie** » Thu Apr 12, 2012 12:11 am

89's are still available. May be too stiff for many users, depending on your plans for armor/bumper.

by **Dirtyd** » Thu Apr 12, 2012 12:20 am

Do the 89's give additional front end lift? Like the z71's in rear

by **hobbstisdaman** » Thu Apr 12, 2012 1:22 am

Yes, But at the risk of having much more of a stiffer ride, unless you plan on evening it off with a steel bumper up front

by **Dirtyd** » Thu Apr 12, 2012 1:28 am

coming from the car world having a dumped Subaru Impreza with about an inch of ground clearance I'm not worried about stiff rides. Nothing can get worse than that, I couldnt even go over speed bumps without scraping.

YouTube Videos · by **Trail X** » Thu Apr 12, 2012 9:35 am

hobbstisdaman wrote:So I found my front springs were 6ac and 7ac. When I looked up those (since they weren't on the list on here) It gave me Front chassis spring 15058529. Which apparently "computer tuned." Does this mean anything extravagant besides me having to figure out the spring rate on my own?

I don't have any record of that spring. Maybe in the later years they revamped the springs a little.

I think posted somewhere there's a rough guide to which spring you likely have based on your vehicle configuration.

Curious - how did you look them up to see which spring you had? I used to use compnine, but they are apparently defunct.

by **hobbstisdaman** » Thu Apr 12, 2012 10:50 am

I went on a rpo "decoder" website and it said: http://www.gm-trucks.com/rpo-code-lookup/?find=6ac. Then I searched that description on google and found this saturn forum http://www.sixthsphere.com/forum/showthread.php/75945-Funny-option-packages. About half way down I saw

that computer tuned suspension was for the people who put 18 inch rims on a saturn with rubber band tires and leave the saturn at factory height.. so gay...

. I Searched special packages for trailblazer and sure enough... There it was from 2007- 2008. The package was completely random selection as well. Calling my "inside man" today to see if the computers had a certain spring rate to tune it too.

YouTube Videos · by **Trail X** » Thu Apr 12, 2012 11:00 am

Still not sure how you linked the rpo to the part number.

All of the TB suspension packages were computer tuned, so that's nothing special nor gay... just the standard.

What do you mean the package was random?

by **hobbstisdaman** » Thu Apr 12, 2012 12:42 pm

I just quoted that guy who said it was gay. I know that they are all computer tuned, but I thought it was strange mine was the only one that stated that with out giving a part number. as for the part number I googled the description on the rpo, http://parts.nalleygmc.com/products/GMC/SAFARI-/SPRING-Front-Chassis/2705482/15058529.html. As far as random. It seems to be that the 6ac and 7ac never had a certain spring rate to measure/design to. I think it was just random(in the since of people like us who don't work for the designer or GM) distribution/tuning.

by **plaen** » Thu Apr 12, 2012 1:55 pm

hobbstisdaman wrote:It seems to be that the 6ac and 7ac never had a certain spring rate to measure/design to.

Doing a little digging on my springs and saw this one for you, 6/7ac is 15125882 from nalley gmc.

15125882 SPRING. Front Chassis
SPRING,FRT - LH. Required: 01
SPRING,FRT - RH. Required: 01
LHD. For: S155 SUSP(6AC),(6JD) (2006-2007) (2006 - 2007).
RHD. For: S155 SUSP(7AC),(7JD) (2006-2007) (2006 - 2007).

On mine, which I dont see listed in the chart is 6dc and 7da

which is listed under 2 part numbers, 6dc is 15125884 or 15125886 for 2002 model years, and 7da is 15125883 or 15125886. Sadly there is no paint or markings of any kind on mine, so i cant give any more info for that.

YouTube Videos · by **Trail X** » Thu Apr 12, 2012 2:02 pm

hobbstisdaman wrote:as for the part number I googled the description on the rpo, http://parts.nalleygmc.com/products/GMC/SAFARI-/SPRING-Front-Chassis/2705482/15058529.html.

That link is a spring for a Chevy Astro or GMC Safari,... not a TB.

The official public description for all spring RPO codes does not list a part number. They all say the same thing - "computer selected spring" or something. You can probably go to a dealer though, and have them look up which spring was installed on your vehicle... just incase you REALLY need to know where you're starting from.

by **djthumper** » Thu Apr 12, 2012 3:37 pm

I think you are better off to get someone to get the build sheet with your VIN number. I know Rob use to do them but I haven't seen him on in a while.

by **hobbstisdaman** » Thu Apr 12, 2012 10:40 pm

I just thought it was strange. I just wanted to know where I was starting from. I just got a build layout today actually.

by **boog2006** » Wed May 16, 2012 11:28 pm

boog2006 wrote:I ordered the moog 81114's.

Lift should be here tomorrow so hopefully I'll get them installed soon. I'll definitely post up

Got these installed...and I'm baffled by the result...combo with markmc 2" gave me 5"...

YouTube Videos · by **Trail X** » Thu May 17, 2012 10:21 am

Are you averaging the left and right numbers?

I'm also not familiar with a 2" lift from Mark. I thought it was 2.5", 1.75", or 3"?

How many miles did you have on your old springs? They may have been sagging a good bit.

Did you drive around after the install before measuring? Things will likely settle a good bit.

by **boog2006** » Thu May 17, 2012 10:59 am

JamesDowning wrote:Are you averaging the left and right numbers?

I'm also not familiar with a 2" lift from Mark. I thought it was 2.5", 1.75", or 3"?

How many miles did you have on your old springs? They may have been sagging a good bit.

Did you drive around after the install before measuring? Things will likely settle a good bit.

Left and right numbers are actually identical now after the lift.

I thought I purchased a 2.5" lift but, actual measurements of the blocks are 1.5" and .5" top spacer?

I have 120k on it and had installed the brush guard also.

Today is the first day driving it, so, we'll see how much it settles and I'll post up.

by **boog2006** » Thu May 17, 2012 11:04 am

Just some comments on the springs...

They are the same overall height but wider, (stock ~4 7/8, moog ~5 1/4)

I had a hard time getting the coil compressors off do to there being more coils on the moods. I had to spin the ends if the compressors around the spring till they reached the bottom coil to get them off. Really did some damage to the spring finish.

YouTube Videos · by **Trail X** » Thu May 17, 2012 11:37 am

boog2006 wrote:I thought I purchased a 2.5" lift but, actual measurements of the blocks are 1.5" and .5" top spacer?

Gotcha. So 2" of spacer = 3" of lift due to the lever arm of the LCA.

boog2006 wrote:I had a hard time getting the coil compressors off do to there being more coils on the moods. I had to spin the ends if the compressors around the spring till they reached the bottom coil to get them off. Really did some damage to the spring finish.

Next time, stick a big screw driver between the coils and pry it open. That's what I had to do. Though the spring finish might not be a big deal, as I understand the Moogs rust pretty fast even with the factory finish.

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