- Sep 2, 2012
- 468
Weather is warming up, I'm gearing up to do a fairly major overhaul on the front end. Started researching parts/sources/threads about 3 days ago, and now I have over 37 tabs spread across 5 browser instances, all full of conflicting outdated info...time to ask for help & input. I KNOW it's long, but this is the summary of 3 days worth of fruitless searching.....
Background:
Truck bought July 2012 with 171,000 km. Have since put another 60k on it. Both front and rear suspension components are OE, except for LBJs & End Links (both Moog, greasable) and AC Delco sway bar bushings. This winter's temperature cycling to extremes, plus the effect of that on local roads, has really taken it's toll. Inner tie rods are shot, control arm bushings are shot, shocks are shot (and may well have been when I bought it!), springs sag 1/2" on left side vs right (front and rear), front struts show signs of leakage, rear end bounces too much, clanky noise from front end is most likely the bushings (end links still tight). ETC....
When I bought the truck, I bought it online based on pics and price. Took a 2 hr train ride to pick it up (didn't finalize deal until after thorough inspection & test drive), and while on the highway drove home, my initial impression was that it was overly isolated from the road and "floaty" - I chalked that up to the subjective difference between my old Montana that I'd driven into the ground with no maintenance and a 7 year newer more upscale vehicle. In hindsight, that may not have been the entire explanation.
I do a pretty consistent 3200km a month, with a pretty consistent 65/35 city highway split. The only day it gets a little rest is Sundays, otherwise it's driven 4+ hours every day. I do no towing, and it's very unlikely for the foreseeable future. Once in a while I load it pretty heavy with astro and photo gear and drive it to some more remote dark sky site. Even though I don't hesitate to travel some pretty rough back country logging and camp roads, they are still roads of a sort - no real offroading, no future intentions on lifting it ( and unwilling to sacrifice the litte gains I did see with the PCM4 tune). Body, power train, interior are all in pretty excellent shape. I can see this vehicle lasting another 5 years with the right maintenance, but that has to be at the right cost
Objective:
Restore front suspension to full health, as cost effectively as possible. I don't want/need soccer mom cushy ride, and while I am a fairly aggresive driver at times, I also don't need the stiffest suspension for high speed cornering - middle of the road seems probably the best approach given driving style, vehicle use patterns, and my own tolerance levels. I am picky as HELL about noise, vibration, squeaks, rattles, bumps and so on.
I have already decided the smartest way to do this is in one fell swoop. I HATE wasting money on labor/time to repeat things that could have been taken care of previously, even if that means replacing a part that doesn't necessarily seem bad at the moment. EG, the UBJs still seem rock solid...but how long can I realistically expect that to last given the age and the miles I put on it. May as well do them while I have it apart.
Ok that should give people enough to go on to begin to address some of the complications I have tripped over while trying to procure the parts - due to length, I'll just start with one, & post others as follow-ons:
Complications/Problems:
1) Monroe quick struts are out, poorly reviewed in general, I personally question the longevity I could expect. I might consider the Moog ST8564, IF I could determine which spring they use. I can't find that info. That's not all that big a deal, since I'm pretty sure I'd prefer going with the aftermarket bilstein's. Further, I found an excellent deal online for a set of 4 Bilstein HD from a Canadian source with free shipping - the deal puts them pretty much on par with the US dollar pricing, and saves me a trip across the border...no brainer if I can just get enough info to pull the trigger...but then I need new springs, mounts and seats. And that may be preferable for a few reasons anyway.
The issue with that is determining the spring that best matches the OE (not interested in surprise discoveries of ride height changes, or drastically different dynamics). GM put out like 9 different spring rates for this platform (various sources for that info, Navigator did a great summary chart on ORTB). As far as I can tell, there are no colored tag remnants left on mine to offer any hints as to what the GM computer selected for my truck when built (relevant RPO codes are 6HD - SUSPENSION ; 7HD - 8HW - COMP RR LH COMPUTER SEL SUSP ; 9HU - COMP RR RH COMPUTER SEL SUSP ; ZW7 - PREMIUM SMOOTH RIDE SUSPENSION). Also as far as I can tell, Moog aftermarket springs basically collapse the 9 GM parts (15125881 thru 15125889) into 4 parts (81110, 12, 14, 16) each covering a slightly different overlapping range
Now, RockAuto has the Moog 81110 and 81112 coil springs available for my XL as a separate set @ ~$60. Both are a 375lb spring rate, Moog just changes the free height to alter the compression amount & load rating. From RA info, the 81110 covers the OEM range of 1512881, 882, 883 springs, and the 81112 covers the 1512883, 884, 885 range of OEM springs. RA also offers a set of ACDelco front coils at twice the price (equivalant OEM 19261980 - no online source I can find gives any detailed description). RA also has Raybestos coils for ~ 50% more money than the Moog. No info on OEM equivalency, but given their 2340lb load rating and 16.74" free height, these would be the equivalent of Moog 81114's which themselves have OEM coverage of 15125885 & 15125886. Interestingly, the Moog 81114's on RA are only $35 a set, but the vehicle fitment is only indicated to be the '02-'06 TB's and the '04 - '06 Ascenders. As a last bit of info, I did see a few complaints on the forums of the Moog springs showing premature corrosion.
As you can see, I chased that for quite a while with no definitive success. I decided to look into the possibility of getting new OEM AC Delco springs, and went to a few GM parts sites where you can enter your VIN # to aid in parts selection. NewGMParts.com matches my VIN to the 881 spring, whereas GMPartsGiant.com insists I have the 15125885's. (My VIN to plugin for anyone who wants to take a crack: 1GKET16S956134882)
I have not yet called an actual dealer to see what they may say. This is partly due to the fact that the main guy at the local dealership is a useless lazy POS who really doesn't give a fuck what he sells/tells people, and the other is that given the vast amount of conflicting info everywhere else, I wouldn't have any confidence in his answer anyway.
QUESTION 1: HOW THE HELL CAN I FIGURE OUT WHAT SPRING I NEED TO CONSTRUCT MY OWN STRUT?!?!?!??!?
2) The Bilstein HD's I have targeted for this vehicle, and available for the deal described earlier, are the B6 4600 series 103336 & 103350. Oddly, both the Bilstein online catalog and their 2014 application guide say these are NOT a fit for XL/EXT models. I have seen some replies to the contrary by knowledgeable forum members here, on the OS an on ORTB. In fact most of the Bilstein DEALERS contradict what Bilstein says, and puts them up as matches for my truck. I'm pretty confident it's the right shock & strut for my application, but there seems to be a distinct lack of LWB guys who have actually used them. I gotta wonder why.
QUESTION 2: IF THE MANUFACTURER DOESN'T SEEM TO HAVE THE CORRECT INFO ABOUT PARTS APPLICABILITY, HOW DID THEY COMMUNICATE SAID INFO TO THE DEALERS WHO CONTRADICT THAT, AND HOW CAN I BE SURE THEY AREN'T THE ONES WITH BAD INFO??!??!
'NUFF for now, I can close at least 15 tabs and start working on the questions of control arms, brackets, bushings
Thx for any input
Background:
Truck bought July 2012 with 171,000 km. Have since put another 60k on it. Both front and rear suspension components are OE, except for LBJs & End Links (both Moog, greasable) and AC Delco sway bar bushings. This winter's temperature cycling to extremes, plus the effect of that on local roads, has really taken it's toll. Inner tie rods are shot, control arm bushings are shot, shocks are shot (and may well have been when I bought it!), springs sag 1/2" on left side vs right (front and rear), front struts show signs of leakage, rear end bounces too much, clanky noise from front end is most likely the bushings (end links still tight). ETC....
When I bought the truck, I bought it online based on pics and price. Took a 2 hr train ride to pick it up (didn't finalize deal until after thorough inspection & test drive), and while on the highway drove home, my initial impression was that it was overly isolated from the road and "floaty" - I chalked that up to the subjective difference between my old Montana that I'd driven into the ground with no maintenance and a 7 year newer more upscale vehicle. In hindsight, that may not have been the entire explanation.
I do a pretty consistent 3200km a month, with a pretty consistent 65/35 city highway split. The only day it gets a little rest is Sundays, otherwise it's driven 4+ hours every day. I do no towing, and it's very unlikely for the foreseeable future. Once in a while I load it pretty heavy with astro and photo gear and drive it to some more remote dark sky site. Even though I don't hesitate to travel some pretty rough back country logging and camp roads, they are still roads of a sort - no real offroading, no future intentions on lifting it ( and unwilling to sacrifice the litte gains I did see with the PCM4 tune). Body, power train, interior are all in pretty excellent shape. I can see this vehicle lasting another 5 years with the right maintenance, but that has to be at the right cost
Objective:
Restore front suspension to full health, as cost effectively as possible. I don't want/need soccer mom cushy ride, and while I am a fairly aggresive driver at times, I also don't need the stiffest suspension for high speed cornering - middle of the road seems probably the best approach given driving style, vehicle use patterns, and my own tolerance levels. I am picky as HELL about noise, vibration, squeaks, rattles, bumps and so on.
I have already decided the smartest way to do this is in one fell swoop. I HATE wasting money on labor/time to repeat things that could have been taken care of previously, even if that means replacing a part that doesn't necessarily seem bad at the moment. EG, the UBJs still seem rock solid...but how long can I realistically expect that to last given the age and the miles I put on it. May as well do them while I have it apart.
Ok that should give people enough to go on to begin to address some of the complications I have tripped over while trying to procure the parts - due to length, I'll just start with one, & post others as follow-ons:
Complications/Problems:
1) Monroe quick struts are out, poorly reviewed in general, I personally question the longevity I could expect. I might consider the Moog ST8564, IF I could determine which spring they use. I can't find that info. That's not all that big a deal, since I'm pretty sure I'd prefer going with the aftermarket bilstein's. Further, I found an excellent deal online for a set of 4 Bilstein HD from a Canadian source with free shipping - the deal puts them pretty much on par with the US dollar pricing, and saves me a trip across the border...no brainer if I can just get enough info to pull the trigger...but then I need new springs, mounts and seats. And that may be preferable for a few reasons anyway.
The issue with that is determining the spring that best matches the OE (not interested in surprise discoveries of ride height changes, or drastically different dynamics). GM put out like 9 different spring rates for this platform (various sources for that info, Navigator did a great summary chart on ORTB). As far as I can tell, there are no colored tag remnants left on mine to offer any hints as to what the GM computer selected for my truck when built (relevant RPO codes are 6HD - SUSPENSION ; 7HD - 8HW - COMP RR LH COMPUTER SEL SUSP ; 9HU - COMP RR RH COMPUTER SEL SUSP ; ZW7 - PREMIUM SMOOTH RIDE SUSPENSION). Also as far as I can tell, Moog aftermarket springs basically collapse the 9 GM parts (15125881 thru 15125889) into 4 parts (81110, 12, 14, 16) each covering a slightly different overlapping range
Now, RockAuto has the Moog 81110 and 81112 coil springs available for my XL as a separate set @ ~$60. Both are a 375lb spring rate, Moog just changes the free height to alter the compression amount & load rating. From RA info, the 81110 covers the OEM range of 1512881, 882, 883 springs, and the 81112 covers the 1512883, 884, 885 range of OEM springs. RA also offers a set of ACDelco front coils at twice the price (equivalant OEM 19261980 - no online source I can find gives any detailed description). RA also has Raybestos coils for ~ 50% more money than the Moog. No info on OEM equivalency, but given their 2340lb load rating and 16.74" free height, these would be the equivalent of Moog 81114's which themselves have OEM coverage of 15125885 & 15125886. Interestingly, the Moog 81114's on RA are only $35 a set, but the vehicle fitment is only indicated to be the '02-'06 TB's and the '04 - '06 Ascenders. As a last bit of info, I did see a few complaints on the forums of the Moog springs showing premature corrosion.
As you can see, I chased that for quite a while with no definitive success. I decided to look into the possibility of getting new OEM AC Delco springs, and went to a few GM parts sites where you can enter your VIN # to aid in parts selection. NewGMParts.com matches my VIN to the 881 spring, whereas GMPartsGiant.com insists I have the 15125885's. (My VIN to plugin for anyone who wants to take a crack: 1GKET16S956134882)
I have not yet called an actual dealer to see what they may say. This is partly due to the fact that the main guy at the local dealership is a useless lazy POS who really doesn't give a fuck what he sells/tells people, and the other is that given the vast amount of conflicting info everywhere else, I wouldn't have any confidence in his answer anyway.
QUESTION 1: HOW THE HELL CAN I FIGURE OUT WHAT SPRING I NEED TO CONSTRUCT MY OWN STRUT?!?!?!??!?
2) The Bilstein HD's I have targeted for this vehicle, and available for the deal described earlier, are the B6 4600 series 103336 & 103350. Oddly, both the Bilstein online catalog and their 2014 application guide say these are NOT a fit for XL/EXT models. I have seen some replies to the contrary by knowledgeable forum members here, on the OS an on ORTB. In fact most of the Bilstein DEALERS contradict what Bilstein says, and puts them up as matches for my truck. I'm pretty confident it's the right shock & strut for my application, but there seems to be a distinct lack of LWB guys who have actually used them. I gotta wonder why.
QUESTION 2: IF THE MANUFACTURER DOESN'T SEEM TO HAVE THE CORRECT INFO ABOUT PARTS APPLICABILITY, HOW DID THEY COMMUNICATE SAID INFO TO THE DEALERS WHO CONTRADICT THAT, AND HOW CAN I BE SURE THEY AREN'T THE ONES WITH BAD INFO??!??!
'NUFF for now, I can close at least 15 tabs and start working on the questions of control arms, brackets, bushings
Thx for any input
)
