Suspension question

[NJTB]

My 2004 Trailblazer has 145,000 miles on it and is ready for new lower control arms, struts, and upper control arms. I wanted to go with AC Delco parts, but they're dammed expensive. Probably will go with AC Delco uni struts as I would like the spring rate to be the same, aren't sure about aftermarket.
So my question is: which aftermarket parts worked best? There's a huge variety on the net, some come as a kit (LCA with the plate, upper control arm, stabilizer links, etc. Moog, Detroit Axle, another brand?
Also, I'm going to have someone put in the LCA and plate as this TB has a pretty rusty frame, might get 3 or 4 years out of it before it goes to the junkyard in the sky, and I'm worried about the bolts on the LCA plate that bolts to the frame.
It does run REALLY well but not used very often.
Any and all advise is appreciated.

 

[mrrsm]

For the sake of seeing the job done while looking over a Mechanic's Shoulder..."The Daninator" arguably has THE BEST Five Part "How To" Series on the Complete R&R of the Front End on a Trailblazer, albeit using a Total Swap from a Donor Trailblazer and with getting some "Must Replace" components. @Mounce, @gmcman and @TollKeeper have some very good insights into the Parts and Procedures on this Big Project as well.

Pay very close attention to the Torque values required on the LCA Plate... You might even want to "Quiz" your Mechanic on this one...just to make certain that he gets this installation RIGHT and NOT guess at this. And as @Mooseman always mentions..."Play these at 1.5Xs Speed via the YT Settings selection...":

 

[NJTB]

Thanks, MRRSM. I'm more worried about decent quality replacement parts.

 

[mrrsm]

I feel you, Brother. This post from 2018 has some additional advice on the Choice of Suspension Parts and I suspect there are many more that can be plumbed in the "Brakes and Suspension" Section:

Suspension parts

Hello guys. I have my 03 Tb due for some front suspension work. As far as replacing control arms upper and lower what brand do you guys recommend. Im looking at Ac delco mevotech and moog. Any experience with these? Let me know my tb will appreciate it.

gmtnation.com

...and Don't forget to check out THIS Link over at eBay for even more 'possibles' if your Budget becomes an issue and you want the Whole Shebang for a Whole Lot Less Money.

Trailblazer Lca Plate for sale | eBay

Get the best deals for Trailblazer Lca Plate at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items!

www.ebay.com

With "0" RUST and the Option to later install your OWN choice of Better Quality Ball Joints and/or Bushings as you see fit, these less expensive but complete components offered on eBay might appeal to you. The New Parts for Buick Raniers sometimes get overlooked as replacements that are nonetheless identical... 'Neath The Skin'.

 

[Maverick6587]

Moog parts are kind of a gamble as they are a worldwide corp. You could order a part and get one that was made in Germany, China, or the US. They all carry the exact same part number. I think they have 13-16 manufacturing locations across the world, the United States is included in those locations.

I plan on redoing my front UCA and LCA next spring. I am going to gamble with Detroit Axle but, that's because I live an hour away from their location and returns should be simple, plus I get to look at the part before I buy it.

The suspension on the other hand... So, AcDelco has about 10 different options for ride stiffness. I would call them and give them the part number you plan to order.

ACD Front Shock Options:
540-149, 540-347, 540-404, 540-411, 540-229, 540-405, 540-128, 540-230, 540-299, and 540-145

If you call ACD, have them transfer you to the suspension dept. The people in that dept can look up each of those shocks and tell you the stiffness of those (above part #'s) compared to the one you are currently planning on purchasing.

 

[TollKeeper]

@MRRSM - Thanks for the honorable mention.

Since you are talking about owning the vehicle in the short term (3-4 years). I would consider just going with Value Options. You can get a kit, that comes with the UCA, LCA, LCA Mounts, Struts, etc, for right around 350ish bucks. Detroit axle is the companies name. They are a ebay company, but I have Detroit axle wheel bearings that are holding up well. There are other members that have them, and the products are good. There have been a couple bad ball joints, but everything else seems to be ok.

Something like this..

Ebay! <--- Edit: This kit will not work, just using it for reference. The LCA is not set up for the 04 Links.

Ebay #2 <--- Edit #2 But this kit should work

UCA, LCA, LCA Mount, Quick Strut, inner and outer tie rod, and UBJ. He has other options as well. Just click on the link, and search his store. I did not show a kit that includes the sway bar links because most of the kits he sells that has them, are for 02-03, and not 04.

The other thing to think about with your rebuild is the wheel bearings. Its not a matter of if, but when, they will fail. And since you are this deep into the rebuild, just get it over with. Detroit axle sells them too.

 

[NJTB]

Thanks for all the replies. After hours on the computer, I wound up going with Detroit Axle upper and lower control arms, and ac Delco uni struts. Now I just have to get the bolts for the strut knuckle and LCA plate.
Maverick, I did call AC Delco for the OE strut options, on mine they are 540-149, but don't come in uni struts. So I guessed. I hope the spring rate is close to stock.
Probably going to be a week or so before I get to this, will keep everyone informed how it goes.
Thanks again.
PS: I did put new hub bearings in about two years ago. Went to Auto Zone, got the mid priced ($100) ones, and they went bad. Went back to AZ, got the high end ones ($150), and they seem to be lasting. To be fair, I wacked a curb pretty hard, not so much to bend a rim or damage a tire, but the bearing went soon after.

 

[Maverick6587]

Were you able to find out the difference in stiffness ratings from the uni strut you want to buy vs. the 540-149 strut that was originally placed on your vehicle?

Careful with coil springs. Most aftermarket coil springs are thicker and taller. I would look up the part number for the coil springs alone from a site like gmpartsdirect or just call your local GM dealership for the part number. Order them online or from the dealer if they're cheap enough.

Rent a spring compressor from AZ or any other local parts store. The job of either swapping out the springs or transferring your old springs to the new front shocks is not very difficult at all.

 

[NJTB]

Maverick
That's the thing, you can't find the spring rate for the aftermarket springs, and compare them to factory springs. At least I couldn't.
The parts are ordered, I damn sure hope I'm at least close.

 

[NJTB]

Also, does anyone have the part number for the strut yoke to lower control arm bolt?

 

[mrrsm]

Not sure if THIS is the Bolt you are referring to…



Image credit via this link to an On Topic TV Thread:
https://forums.trailvoy.com/showthread.php?t=47915

...but this information on the GM OEM Suspension Bolts Dimensions comes from @Reprise via this Thread and may work for this Strut Yoke-to-LCA application:

https://gmtnation.com/forums/threads/lower-control-arm-bolt-size.15628/

11518576
M16 x 2 x 70

Two of these OEM Bolts are presently available from RockAuto:



https://www.rockauto.com/en/parts/general+motors,11518576,bolt,1000374

Regarding the LCA Torque Procedures, this comes courtesy @seanpooh via this Thread:

https://gmtnation.com/forums/threads/lower-control-arm-bolt-size.15628/

“Tighten the front lower control arm bracket mounting bolt to 265 N·m (195 lb ft).

• Tighten the rear lower control arm bracket mounting bolts to 240 N·m (177 lb ft). Install the lower control arm to the lower control arm bracket.
  
  Install the lower control arm to lower control arm bracket mounting bolts.
  
  Important
  
  Ensure that the lower control arm is parallel to the lower control arm bracket during the installation and tightening of the lower control arm mounting bolts and nuts. This will ensure correct alignment of the lower control arm bushings.
  
  Install the lower control arm to lower control arm bracket mounting nuts.
  
  Tighten the nuts to 130 N·m (96 lb ft). “

GM OEM fasteners are very hard to come by. So even if these (2) available GM OEM Bolts may NOT work on the Strut Yoke-to- LCA... Having them with your R&R Kit will not hurt if they are better than the ones you will remove from other locations on the suspension.

 

[Reprise]

Yes -- the strength, length & thread pitch are the important things. Not so much the source (OEM vs *reputable* vendor).

If a grade 8 bolt (as an example) was originally used, it's there for a reason, so replace with same.

The tricky ones are when the OEM bolts are tapered, etc., to aid in assembly. There are ways to duplicate that, if required. But that's about the only time I concern myself with an OEM sourced bolt, should one break, it's spec'd for one-time use, etc.

 

[TollKeeper]

Are you talking about where the lower strut arm connects to the lower control arm? Or are you talking about where the strut and the lower strut arm connect at the pinch bolt?

The bit bolt at the control arm will come with the new control arm, and I believe a new nut comes with that assembly from Detroit Axle. If you are talking about the pinch bolt, some times they come with the strut when purchased, sometimes they dont.

 

[TollKeeper]

I just ran across a product that might help with your rusted nuts and bolts. I have not tried it, but looks to be interesting..

Freeze Your Nuts Off! (Yes its a real link)

 

[NJTB]

Thanks again guys. I went to the dealer yesterday and ordered the LCA bracket bolts (6bolts, $50, ouch), and found out the strut yolk to LCA bolt was part of the LCA assembly. Came home and checked the order, looked at the pictures, and it's there. Whew.
Tollkeeper, thanks for confirming.

 

[AbleDanger]

I too second the Detroit Axle LCA. I put mine in about 10k ago. Good quality for the price.

Also, for rusty bolts (mine has 170k in Cleveland/Northern Indiana salt), I too suggest a freeze product like Tollkeeper suggested. I replaced the exhaust manifold earlier in the summer because of a broken O2 sensor and used a freeze product. It was CRC Freeze off. I didn't break one bolt and have used it on anything rusty since and it is a godsend. The bolts came out like they were brand new. The trick is to use it on the bolt, not the nut since it shrinks the metal. I found my can at Autozone and no one seemed to know what it was since I think it is rather new. I am going to buy a few more cans and it has worked better than anything else I have ever used (heat, penetrating oil, etc).

 

[mrrsm]

If these New, High Quality Bolts cannot be located... There is an alternative to try that, at the very least, will passively and with absolute certainty, completely remove ALL Rust from them, virtually overnight.

Just gather up all of those Old Fasteners, then use Brake-Kleen to first De-Grease them and finally, submerge them is a container with THIS stuff. You might find them completely serviceable after removing them from this Non-Toxic "EVAPO-RUST" Chemical Bath, wiping off the Ferric Carbon Residue and re-use the ones that can pass your visual inspection for any loss of Metal and Strength:

Available for just under $8.00 in a (32) Ounce Container on Amazon:

Amazon.com: Evapo-Rust, The Original Super Safe Rust Remover, Water-based, Non-Toxic, Biodegradable, 32 oz: Automotive

Buy Evapo-Rust, The Original Super Safe Rust Remover, Water-based, Non-Toxic, Biodegradable, 32 oz: Tools & Home Improvement - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[NJTB]

Thanks for the 'freeze out' and 'Evaporust" suggestions. I'm truly apprehensive of the bolts on the LCA bracket, as if they break, I don't have any way of removing them from the frame. My go to for these sort of things was a torch with a rosebud tip, but don't have one anymore.
Also glad to hear Detroit Axle works well.
The parts arrived yesterday, the LCA and bracket has no manufacturing country on it, the uppers are made in China. Damn.
Going out to the garage soon and installing the struts and UCA's, next week I'll get to the lowers.
Again, thanks all.

 

[2001ZR2]

You can get evaporust at Harbor Freight if time is a factor.

Spray with penetrating oil the LCA bolts for a few days before and the hear probably won't be needed.

I put Detroit Axle wheel hubs on my son's ZR2 blazer and they seemed to be well made. The ABS sensors work as there are no more ABS codes/light.

I have rebuilt two of these front ends in the last year on my wife's Envoy and my other son's 05 TB.
It's not too hard especially using the complete LCA as the only struggle I had was getting a lower ball joint out on each. A good ball joint press and accessories combined with the CRC freeze off let me complete the task. Also a BFH well help.

Remember to scribe a mark on the LCA pocket so you are close.

 

[mrrsm]

Small h/j...

With the understanding that Damaged, Destroyed or Lost Automotive Fasteners for many R&R Jobs can be damned near impossible to come by... Having a site like THIS one to go to can be a Project Life saver. It would not surprise me if the ones needed here can also be found at this place. Worth a Bookmark:

https://autofastenersandclips.com/collections/gm-automotive-fasteners

 

[sunliner]

I recently did LCA's among other things on my 06. soaked the bracket to frame bolts in PB Blaster for 4 days before I did the job and they came out pretty easy. Had to do the bolts over because I didn't have the right wrench the first time. I've never cranked on anything with torques this high before...got really nervous waiting for the wrench to click, given that these bolts are almost certainly the original ones from when she came off the assy line, but all appears to be good

 

[NJTB]

Finally got it done.
The LCA bolts were a bit thin on the neck, rusted away. The guy I took it to heated the frame side of the nuts and they came off without breaking. Whew. I ordered the stabilizer links from Amazon (Moog) and of course they sent me two lefts, so I had to buy them again. No big deal.
Took it to the alignment shop, told them it was probably going to be a tough alignment (it was), they spent about a half day on it. Still just charged $95 for it.
The repair definitely tightened up the front end, drives real well now.
Now onto the rusty trailing arms and panard bar. Stay tuned.
Thanks again for all the support and advise, you guys made a miserable job bearable.

 

[Traz 2.0]

This is a bit off topic but what do you call this part? I keep looking for it but anytime I describe it no one seems to know what I'm talking about (Sorry I stole your pic mrrsm)

 

[Maverick6587]

@Traz 2.0 That's the Yoke. I would only replace that with the LCA. It's a bitch to get off of the LCA.

15743860

Yoke

 

[NJTB]

This is a bit off topic but what do you call this part? I keep looking for it but anytime I describe it no one seems to know what I'm talking about (Sorry I stole your pic mrrsm)

You can look them up on Amazon, Ebay, rock auto, etc. They are expensive. It's called a strut yolk.

 

[Mooseman]

There are a couple of ways to get it off the LCA. You can use a Pitman Arm puller or a ball joint pickle fork. I have also had success with just wacking it with a BFH, which is the same idea as with tie rods and ball joints from the vibrations.

 

[sunliner]

There are a couple of ways to get it off the LCA. You can use a Pitman Arm puller or a ball joint pickle fork. I have also had success with just wacking it with a BFH, which is the same idea as with tie rods and ball joints from the vibrations.

is this for getting the yoke off? apparently my lower ball joints are bad. debating trying to replace just the ball joint vs the whole lCA, just replaced the LCA brackets, so I'm familiar with most of the procedure, except removing the yoke.

 

[Mooseman]

is this for getting the yoke off?

Yes, from the LCA.

Pittman arm puller for struts

I tried doing a search on this but couldn't find the answer. I going to buy a pitman arm puller for the fron struts but from what I hear there are two different pitman sizes. Would anyone be able to tell me excactly which size puller to get?

gmtnation.com

 

[AbleDanger]

I replaced the whole LCA but to get the yoke off I had to cut the bolt on the old LCA, put it in a 20 ton press and heat it with a torch. It took a lot of force. Pittman arms and pullers did not work in my case, nor did soaking it for days with penetrating fluid. If the bushing that connects the yoke to the LCA is in good condition, I would suggest just pressing in a new ball joint into your current LCA. Cleveland salt made this a big job.