Ball joints + upper control arms replacement. Any tips?

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Tachyon

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On my 1999 K2500 Suburban (with forged lower control arms) I'm going to replace the upper and lower ball joints on both sides. I went ahead and bought the full new upper A arm kit from Rock Auto with included ball joints since it was pretty reasonable and I'll then have new A arm bushings as well. Went Moog for all the parts.

Any tips, tricks or caveats I should know about with this job?

Oh, and does anyone have a source for torque specs for the fasteners involved in this job or for the front end in general?

Thanks in advance!!



CP GMTC
 

Schurkey

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Rubber control arm bushings means you'll be torquing the bolts that go through the control arm bushings with the suspension at normal ride height. GM calls this the "Z Height". Frankly, I think it's a mistake to not use Polyurethane bushings which can be torqued in any convenient position.

All torque specs and the "official" Z height measurement and measurement procedure are in the official GM service manual you should have.

"While you're in there dicking with the control arms anyway", you should replace the lower control arm bushings, the sway-bar end links, any loose joints such as tie rod ends, idler arm, pitman arm, LUBE ALL THE (steering and suspension) JOINTS, check the sway bar bushings, boots on the CV joints, shock absorbers, check the brake pads and rotors, and AT LEAST FLUSH the brake fluid and verify that the brake hoses are usable (rubber not cracked). Take a look at the rag joint on the steering gear, too.

When it was me, I blew the brake caliper pistons out, cleaned the pistons and pried the crust off the caliper seals with my fingernail, lubed the caliper mount rubbers, and then slapped the calipers back together without buying any parts--just cleaning what was already there. The caliper pistons moved noticeably more easily afterwards.

If you have non-welded alignment eccentrics on the upper arm, you'll want to at least make precise note of where they're positioned so you can put them EXACTLY where they were before you took them apart. Getting a proper wheel alignment would be even better, and pretty-much essential if you replace any of the tie rod ends.

If your eccentrics are welded like mine are, you can choose to cut them free or leave them the hell alone. I left mine where they were. "Alignment" then consists of nothing more than adjusting the toe, and thereby the steering-wheel straightness.

https://www.gmt400.com/threads/front-end-overhaul.45214/
All of it's good, but especially beginning at Post 24.
 
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Tachyon

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Rubber control arm bushings means you'll be torquing the bolts that go through the control arm bushings with the suspension at normal ride height. GM calls this the "Z Height". Frankly, I think it's a mistake to not use Polyurethane bushings which can be torqued in any convenient position.

All torque specs and the "official" Z height measurement and measurement procedure are in the official GM service manual you should have.

"While you're in there dicking with the control arms anyway", you should replace the lower control arm bushings, the sway-bar end links, any loose joints such as tie rod ends, idler arm, pitman arm, LUBE ALL THE (steering and suspension) JOINTS, check the sway bar bushings, boots on the CV joints, shock absorbers, check the brake pads and rotors, and AT LEAST FLUSH the brake fluid and verify that the brake hoses are usable (rubber not cracked). Take a look at the rag joint on the steering gear, too.

When it was me, I blew the brake caliper pistons out, cleaned the pistons and pried the crust off the caliper seals with my fingernail, lubed the caliper mount rubbers, and then slapped the calipers back together without buying any parts--just cleaning what was already there. The caliper pistons moved noticeably more easily afterwards.

If you have non-welded alignment eccentrics on the upper arm, you'll want to at least make precise note of where they're positioned so you can put them EXACTLY where they were before you took them apart. Getting a proper wheel alignment would be even better, and pretty-much essential if you replace any of the tie rod ends.

If your eccentrics are welded like mine are, you can choose to cut them free or leave them the hell alone. I left mine where they were. "Alignment" then consists of nothing more than adjusting the toe, and thereby the steering-wheel straightness.

https://www.gmt400.com/threads/front-end-overhaul.45214/
All of it's good, but especially beginning at Post 24.


Good stuff, thanks.
Don't have an FSM, so that's why I was asking about torque specs.
I did a complete brake job in the fall so just planning a minor inspection there. Put in new Pro Stop brakes, including new calipers.
As for the rest, I'm planning to do this in two parts (I know, but that's how I need to split it time and money wise). First the U/L Ball Joints and U control arms this job.
Then next time around, my plan is to unbolt the entire steering assembly. Centre link, tie rods/ends , sleeves, idler arm, pitman arm. All as one unit. Put the whole assembly on the ground. Use it to set the rough alignment on an all new assembly, bolt that back in. Then take the whole thing for an alignment.

Gonna check out that link now....thanks!
 

Tachyon

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Unfortunately that other thread, though very interesting and informative, mostly relates to the 1500 models with the stamped lower control arms.

Mine is a 3/4 ton with the forged lower control arms. I'm guessing they have different torque specs.
 

df2x4

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Get a set of FSMs, for real. They're awesome. This is from my '97 set.

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Tachyon

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Thanks!
Any suggestions on a reasonably priced source? Do most people get them from ebay or what?

Meanwhile, I went and bought the Haynes online version for my truck which did have all the torque specs, though the actual replacement procedure pages are a little weak. But I have enough to manage I think.

I've decided to put the job off for a little longer. I'm going to save and order the rest of the front end and do it all at once. IE tie-rods, idler/pitman arm, centre link, etc.


Does anyone have any thoughts on these types of "service manuals"
https://ebay.us/ZJs0ZL
 
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Tachyon

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Oh, for future reference, in case anyone else needs this info...


Part or connection -- Torque (ft-lb)
Upper control arm-to-frame nut -- 140
Lower control arm-to-frame nuts -- 121
Balljoint-to-control arm bolts -- 17
Lower balljoint-to-knuckle nut -- 84
Upper balljoint-to-knuckle nut -- 94
Driveaxle nut-to-hub and bearing -- 165
Hub & bearing assy-to-steering knuckle -- 133

WARNING -- These specs apply specifically to my year, model, and weight rating vehicle ONLY!

That means a 1999, 3/4 ton, Suburban 4x4 with 5.7l (originally) and 8600 lb GVWR.

There are a lot of variations among the GMT400 platform by vehicle, year, 2 or 4 wheel drive, etc.

I make no guarantee as to the accuracy of these specs and will not be accountable for typos or inaccuracies. Use at your own risk.
 

df2x4

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Thanks!
Any suggestions on a reasonably priced source? Do most people get them from ebay or what?

Check Helm Inc. (the original publisher for GM) first to see if the set you need is still in print. If it is, chances are you can get it new from Helm for cheaper than a used set on eBay.

https://www.helminc.com/helm/homepage.asp?

If Helm doesn't print them anymore, then eBay is probably your best bet.
 

Tachyon

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I contacted Helm Inc., they no longer stocks anything for my vehicle.

I bought an electronic version of the FSM off e-bay. It seems slightly shady, but it is the real deal as far as the data and software on the DVD.

Cost me $16.95 USD + $15 S&H and import fee.

Can't complain.
 

Tachyon

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Get a set of FSMs, for real. They're awesome. This is from my '97 set.

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Thanks for this. It helped itself and it also confirmed that the electronic FSM I received is legit since the corresponding pages match up.
 
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