GMT800 steering box into GMT400

[dfarr67]

Not a lot of info out there- feel free to add your experience. Just installed a 2005 Tahoe Z71 Delphi (4 bolt input cover) into my 1989 K1500. I did not remove this myself but requested it online and was assured this was the part I wanted, all I was told was that there is a difference in Pitman arm between 1/2 ton and heavier GVW vehicles. There are some remarks to get the frame bolts as well- I used my old bolts as the newer ones were too long. Hoses fit no problem, I did have to purchase an adapter from Borgeson and grind a flat to fit the oe steering shaft to the box. I tried to save my ACD Pitman arm but it didn't oblige during removal and I ended up using the original that came with the steering gear.

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[dfarr67]

Because of the extra 2 inches of the adapter- the plastic dust shield will no longer fit.

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[454cid]

So what was the purpose behind this?

 

[dfarr67]

I've had steering/pump issues for years and I decided to throw a seal kit at a Caddy SUV hydroboost configured pump and baseline that as well with the system. Fair disclosure- the front diff is out for rebearing and seal job so no road test so far, but after purging the system on jack stands- no funny noises so far.
Years ago this truck handled extremely well...until the steering gear plain wore out. I sent the oe core down to Tom Lee to redo and lighten the feel slightly- HE did a fabulous job......until one of the top plate bolts pulled its threads and oil started puking. (I should have studded/heli coiled or JB'd the bolt because what came next was a nightmare). By this time Tom had moved on to retirement and the new owner wasn't going to honour any warranty- we came to an agreement to fix the unit....so on top of the initial expense plus more shipping (to and from Canada) and another $100 I got the POS back. Steering was whiny when hot and the truck actually overheated the PS on a chassis dyno with oil spraying everywhere tried all kinds of PS fluids and lost count of pumps as I couldn't believe the box was the problem (Lee built-right?), won't be spending THAT kind of money for disappointment any time soon, I've sourced a good used oem piece and have high hopes.

 

[dfarr67]

So what was the purpose behind this?

Question from a guy who hasn't had steering gear issues? The boxes are generaly NOT on the radar when functioning properly- when a quality replacement is needed.....the fun and games start.

I needed a box- Saginaw supply is getting old and worn out- reman's have a spotty record. Tried a 'step up' and failed. This seems to be a good alternative. 00-05+ Delphi (06+ the Pitman arm may have differences in splines and there was a change to rack), three bolt version in virtually all 1/2 tons is a 670? series, heavier four bolt 680? series in other models.

 

[Cadillacmak]

Needed a box- Saginaw supply is getting old and worn out- reman's have a spotty record. Tried a 'step up' and failed. This seems to be a good alternative. 00-05+ Delphi (06+ the Pitman arm may have differences in splines and there was a change to rack), three bolt version in virtually all 1/2 tons is a 670? series, heavier four bolt 680? series in other models.

Thanks for posting this, it will help someone at some point (maybe me). I know some people want to keep it all original, but not me, I like upgrades.

 

[KansasOBS]

Interesting. I swapped in a delphi box out of a 2004 2500HD, and it was basically the same as the saginaw. Wonder what the technical differences are in the box you used, cause its not.

NBS steering box and shaft mod. (3500/2500HD related)

Hello all, been a bit since Ive been around. The steering box on my truck decided to start making a mess of itself, pretty sure it was bad from the get go OBS donor truck. Anyhow I tore into my extra that had been in the dually, without a hood for years. Thought I would rebuild and swap it, but...

www.gmt400.com

Though it turned out that in my case I was an idiot. I thought the input shaft was leaking, but had a tiny hole in the front brake line. Should have known better.

 

[dfarr67]

Thanks for posting this, it will help someone at some point (maybe me). I know some people want to keep it all original, but not me, I like upgrades.

The 'upgrade' was the original Lee box, I was very happy with it for a few months. These days just to get oem quality back in the truck is difficult.
Original
- 385 cid TPI
- hydroboost with 2005 subby brakes front and back, etc.
- bad pic

 

[dfarr67]

Interesting. I swapped in a delphi box out of a 2004 2500HD, and it was basically the same as the saginaw. Wonder what the technical differences are in the box you used, cause its not.

NBS steering box and shaft mod. (3500/2500HD related)

Hello all, been a bit since Ive been around. The steering box on my truck decided to start making a mess of itself, pretty sure it was bad from the get go OBS donor truck. Anyhow I tore into my extra that had been in the dually, without a hood for years. Thought I would rebuild and swap it, but...

www.gmt400.com

Though it turned out that in my case I was an idiot. I thought the input shaft was leaking, but had a tiny hole in the front brake line. Should have known better.

I know it says Delphi on your box, I'll call it a Saginaw with the cover at the bottom. Been told the newer ones are valved different.

This has a few nuggets.

Steve, my 1995 K1500 Cowboy Cadillac.

So I've been on this forum since it started, and it's about time I made a build thread. My truck has seen a lot of changes since I got it. I purchased this truck back at the tail end of Cash for Clunkers back in August of 2009. We needed a truck to do stuff for the house and move things around...

www.gmt400.com

I was specifically after 00-05 Tahoe/Yukon Z71 boxes (there may be other models that are the same- Suburban/Avalanch Z71..I don't know) they are a heavier box like in the 2500's but supposedly have a nicer ratio. Lots of Saginaws in those years as well, but I was told the Delphi was a more modern design.

 

[Caman96]

Question from a guy who hasn't had steering gear issues?

It’s a forum…sometimes people have questions, it’s not Facebook.