Rebuilding a steering box

[Matthew Jeschke]

Went to have a my 2001 Z71 Tahoe aligned. One of the FEW places I've not rebuild is the steering box. There's ZERO play in front suspension / steering joints. However, the steering wheel seems a little spongy. I kind of thought was normal performance as it doesn't clunk or anything. However, I drives differently than my buddy's 2005 Z71 silverado. Turning is not as confident. The shop couldn't find center on the steering wheel with relation to the wheels for alignment though. The said the steering box needs rebuilt...

Long story short, has anybody rebuilt one of these steering boxes. I'm going to take the job on but don't know exactly what to order. I see there are various different kits with different parts.

 

[exp500]

You might find a service manual for it at these links-

Helpful Links

Helpful links- If this is a successful post maybe it could be stickied! Here's the first- https://www.gmt400.com/threads/88-95-service-manuals.43575/ https://67-72chevytrucks.com/vboard/showthread.php?t=700011

www.tahoeyukonforum.com

The most important section is the front adjustment under domed cover. That determines the torque load before movement begins. Stay on hi side.Inspect gear closely. That is usually the issue. Someone here has the wrench, doublelieve or swathdiver or east302 if I remember correctly. Ebay is also an option.

 

[Matthew Jeschke]

I talked with a friend who is a ASE mechanic. He said, he thought there's an adjustment screw to take the play out of the wheel. Anybody familiar with that procedure? Maybe I don't need to tear it down. It's not leaking, just a little loose.

 

[George B]

I talked with a friend who is a ASE mechanic. He said, he thought there's an adjustment screw to take the play out of the wheel. Anybody familiar with that procedure? Maybe I don't need to tear it down. It's not leaking, just a little loose.

Yes sir! Did that on my 03 Burb. I placed an allen wrench in the adjuster, noted the location and loosened the jam nut while holding position of the adjuster. I think I went almost a half turn tighter maybe more. I just adjusted and test drove it until it felt better. Then I resisted the urge to go further. Drove almost another 100k after that.

 

[Matthew Jeschke]

I tightened mine 2 turns. Seemed like a lot... I simply grabed the input shaft and wiggled it as I tightened until the slop was taken up. Then I backed off and VERY lightly tightened then set the lock nut making sure it didn't turn further.

I saw a video on youtube where the guy said to tighten that set screw to 3 ft lbs (finger tight). I couldn't find the rebuild manual for the gearbox though. So hopefully I didn't over do it!

It feels good driving though. About like I'd expect from a truck. Before was just loose. It would respond going down the highway, but was SUPER easy to turn the wheel. When stopped, you could wiggle the steering wheel. Not quite like other vehicles I'd drove with bad steering but just loose feeling. Another truck I drove didn't turn at all till I took up slop in the wheel. Mine never did that.

Anyways, I think I got it. Just hopefully didn't over do it.

 

[Matthew Jeschke]

What would be fun to know is what the make, model, etc. of the gear box is. I think is a "Saginaw" box? I don't know a lot about these. I may buy a second one from the junkyard and rebuild it.

I think the fact I had to turn in the setscrew that much means the bearings are heavily worn.

Putting notes below...

I watched this:

Here's a guy rebuilding a gearbox from 2003 Z71 tahoe:

This is where he talked about 3 ft lbs on the set screw.

Found this:

How To Identify Your Steering Gear Box - Lee Power Steering

Our comprehensive guide will help you identify your power steering gearbox. We sell & service 5 different Saginaw gearboxes: Saginaw 800/808, 708, GMT & Ford.

leepowersteering.com

and this:

Saginaw Box Rebuild - How To!

www.pirate4x4.com

Guy in one of videos said rebuild procedure for older Saginaw box is in this book, although wouldn't be for my truck:

1987 Oldsmobile Chassis Service Manual Volume 1 & 2 88 98 cutlass ciera calais | eBay

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Exploded Diagram:

Adjusting procedure for Saginaw box:

https://images.carid.com/agr/items/pdf/gear-box-adjustments.pdf

 

[exp500]

Check above links, Look for Unit Repair Manual ST333 88 1998 may be close enough to be helpful.

 

[Matthew Jeschke]

Now I'm maybe in a pickle haha

So when I drive the truck, I can let my hands off the wheel and it doesn't return to straight. It comes close but not all the way (maybe within a 1/5 of the way).

I decided to loosen up the set screw a bit... We'll I now notice, it doesn't matter if I loosen it, or tighten it. The steering feels the exact same. It's super weird. So I COMPLETELY loosened the screw and locked the nut. Hopefully it will loosen the steering back up, then I can repeat the procedure?

 

[Matthew Jeschke]

I think the truck came with a Saginaw 670 Gearbox. I finally found some info in the Factory Service manual.

 

[Matthew Jeschke]

FYI, if anybody else does this in the vehicle. You should REALLY lift the front end off the ground so you have only resistance of gearbox when testing play in the wheel. I lifted my front end up, spun the adjuster all the way up / out / loosest position, and my steering is REALLY stiff. I put a mechanic's stethoscope on the gear box and spun steering wheel with engine running and not running. Both had no ill sounds... but something must have bound up in the box during adjustment. I cannot quite figure it out now. The box still functions but has me nervous. I may just buy another gearbox.

 

[Matthew Jeschke]

I'm STILL adjusting lash on my steering box. Slowly but surely. It's a hobby truck. I go out once a week in mountains exploring. Each time I tighten the set screw a 1/8th turn. It's getting better! I should have never loosened it all the way. I may also have a loose pitman arm.

 

[exp500]

Matthew- There is a tray of sorts connected to the Adjustment bolt. This guides the recirculating balls. I adjust them 1/8 turn at a time like you, but with eng running. Then I can hear if it goes "on Pressure" while tightening. Still have to test for balls binding though. Good luck These boxes are tough for what they do.

 

[George B]

I also made small adjustments at a time until the steering was better. The challenge is to stop when it’s “good enough” before it’s “too far”.

 

[Matthew Jeschke]

Latest loot from junkyard. Looking forward to rebuilding this bad boy

 

[Matthew Jeschke]

I need to order a rebuild kit. Not exactly sure where to get a good one for the steering gearbox.

Next I want to order a new power steering pump... might as well, I have 250,000 miles but I see there are multiple different pumps. Not sure if I have; hydroboost?

 

[Fless]

Post a pic of your master cylinder

 

[Matthew Jeschke]

I watched a handful of rebuild videos on Youtube for saginaw steering boxes. Only one found on a Z71 (will update post above with notes to include that).

I ordered this rebuild kit here after combing over RockAuto

More Information for GATES 348526

Also ordered a new pitman arm and idler arm. I think mine may have some play in them as I get a ever so slight wiggle when pulling on steering bar.

More Information for MOOG K6536HD

More Information for MOOG K6534

Was sorted about Moog or Mevotech. I bought Moog ball joints for control arms and the boots fell apart. The moog arms were a few more dollars than Mevotech. However, I ordered the moog.

@Fless Pictures of master cylinder... Is that a hyrdroboost? Curious is it something would be good to upgrade to if not?

 

[Fless]

That's not hydroboost, it's a vacuum booster. There are some Youtubes on converting to Hydroboost, and doing that would take a different power steering pump along with the other hydroboost parts.

 

[MassHoe04]

With higher pressure, anyone converting to Hydroboost might want to plan on replacing old brake lines and add stainless braided hoses...

This article says pressure can be nearly double with Hydroboost.

"Hydroboost systems are also capable of delivering significantly greater pressure through a braking system than a vacuum boost. In some cases, you can more than double the pounds of pressure being distributed to your brakes simply by opting for hydroboost."

Some lines and hoses might already be on the edge of being able to contain regular pressure from the vacuum boost system, let alone double the pressure. Fluid could blow out big time, if added to a fragile distribution system.

Full article for fun reading...

Hydroboost Brakes: Why Your 4x4 Truck Project Deserves A Stopping Power Upgrade

Hydroboost provides an across-the-board upgrade that will have you wondering why you lived so long in the world of traditional vacuum-boosted designs.

www.drivingline.com

 

[Tonyrodz]

With higher pressure, anyone converting to Hydroboost might want to plan on replacing old brake lines and add stainless braided hoses...

This article says pressure can be nearly double with Hydroboost.

"Hydroboost systems are also capable of delivering significantly greater pressure through a braking system than a vacuum boost. In some cases, you can more than double the pounds of pressure being distributed to your brakes simply by opting for hydroboost."

Some lines and hoses might already be on the edge of being able to contain regular pressure from the vacuum boost system, let alone double the pressure. Fluid could blow out big time, if added to a fragile distribution system.

Full article for fun reading...

Hydroboost Brakes: Why Your 4x4 Truck Project Deserves A Stopping Power Upgrade

Hydroboost provides an across-the-board upgrade that will have you wondering why you lived so long in the world of traditional vacuum-boosted designs.

www.drivingline.com

I have hydroboost in my Express van and love it. Van stops great, and it's very heavy.