Stock steering box? Dealer blows

[Scottmclearn]

So here’s some details,

1994
Gmc3500
4wd 6.5 manual trans
Ext cab long bed

My question is. The truck is 3500 not a dually. Dealer says I have a 10,000lbs steering box. Same as a 3/4 ton? Is that because It’s a single rear wheel?

I looked up the two boxes specs side by side and the only difference is the turns to lock. 10,000lb box is 3 15,000lbs box is 4. If I put a 15,000lb box in will it work?

 

[454cid]

The 15000lb truck would the the 3500HD, which is not a pickup, and was more related to the P30 chassis. It was basically a small medium duty truck. It was 2wd only (except for conversions) and would have gone to an up-fitter for a dump box, or be converted to a tow truck, or something.

The heavy 3/4 and 1-ton are basically the same truck... spring rates will be different and maybe brakes. The light 3/4 is basically the same as the 1/2 ton, with some upgrades rear axle and brakes again.

I would guess the 3500HD box would work, but I don't know that. The 3500HD chassis is completely unrelated to your truck, and I see no benefit to it. Why do you want it? It's probably just a lower ratio.

 

[Scottmclearn]

The only reason I thought about buying it is because, it’s cheaper no doubt because of how many were produced

 

[sewlow]

Searched part numbers at NAPA (www.napaonline.com)

The same basic steering gear design is used on 1988--2000 vehicles including C/K pickups, Suburban, Blazer, Yukon, Tahoe, and even some Dodge Ram trucks, including 1/2, 3/4, and 1-ton vehicles.

In my search, four part numbers show up for these vehicles from 1988 to 2000. All have three mounting bolts, the same plumbing threads (M18 X 1.5; M16 X 1.5), the same size input shaft (3/4"), the same diameter output shaft (1 1/4") and the same spline count (32). In short...interchangeable.

NSP 88278091 = the one originally specified for my truck (88--95 C/K1500, and others)
Gear box turns = 3 1/16

NSP 88278117 = 1996 C,
Gear box turns = 2 5/8
The 'Sport' box. 454SS, + various Tahoes & Suburbans. GM recommends not to be used in a 4x4 app. Something to do with higher C/G and over-correction during evasive maneuvers. Ehhh...I dunno. ...and yet I've read other's posts on here, years ago, mentioning something about wanting the slower box (more turns) for the extra leverage it provides at slower speeds when 4-wheeling. O.K. Sure. I'll buy that! Lol!

NSP 88278090 = 1997--2000 C/K, various Suburban, Tahoe, Ram
Gear box turns = 3 -- 3 1/2

NSP 88278127 = 1999--2000 Escalade, 1998-1999 C/K and Suburban, 1998--2000 Tahoe
Gear box turns = 3 1/16

www.napaonline.com does not list information such as torsion bar diameter and gear RATIO. Implying gear ratio from the gear box turns lock-to-lock is extremely imprecise because some steering boxes have internal stops and others don't.
Boxes without internal stops rely on the steering knuckle bumping against something (typically a reinforcement on the lower control arm) to limit steering travel.
The 4x4 boxes, I suspect, (& I may be wrong!) are not internally-limited, and the various chassis designs determine the turns lock-to-lock.

That's the only thing that makes sense to me, because the boxes shouldn't have more than one figure quoted for turns otherwise.

Unless you're gonna be doin' some wheelin', I'd go with the tighter box (wait...what? Well, of course! Always! Anyways...) or the #XXX127

 

[454cid]

Searched part numbers at NAPA (www.napaonline.com)

The same basic steering gear design is used on 1988--2000 vehicles including C/K pickups, Suburban, Blazer, Yukon, Tahoe, and even some Dodge Ram trucks, including 1/2, 3/4, and 1-ton vehicles.

No, there is a GVW split. There's a big box and a small box.

Interesting notes you made on the internally limited vs. chassis. I'm sure my truck is chassis limited, as the knuckles are slightly deformed from contact with the forged lower arms.

 

[454cid]

The only reason I thought about buying it is because, it’s cheaper no doubt because of how many were produced

The box for the 3500HD is cheaper? That's odd. I doubt there are more of those than regular 3/4 and 1-tons.

 

[gstubbz]

The 3500HD box appears to be the same size and mounting points as the normal GMT400 stuff. I think it probably has more turns in it as you can get an HD to turn sharper due to the wider axle. I'd personally go with the NSP 88278117 box though as I like less turns.

It could be cheaper due to demand, since 98 of 100 people going in for a steering box need it for a normal truck/suburban/tahoe/etc and 2 people are looking for a part that is made for an HD.

 

[454cid]

It could be cheaper due to demand, since 98 of 100 people going in for a steering box need it for a normal truck/suburban/tahoe/etc and 2 people are looking for a part that is made for an HD.

That's the exact opposite of how things usually work.... usually specialized stuff costs more so it's worth while to keep a slow moving product on the shelf.

 

[Jared Jackson]

That's the exact opposite of how things usually work.... usually specialized stuff costs more so it's worth while to keep a slow moving product on the shelf.

Retail auto parts:
Customer: I need a ECM for a 2012 Kia Rio today!
Parts dude: It's special order, 600+ttl and I can have it in a month.
Customer: That's outrageous!
Parts dude: ¯\_(ツ)_/¯ It's a Kia!

If they don't sell them regularly, they are not stocked. If the part is not in high demand... it's expensive! I would think the HD box would be pricey and other one would be affordable with a decent core charge because of the demand for rebuilds.