[scott-462]

I've been reading up on steering box swaps and sounds like the 92-98 jeep grand cherokee box is the most mentioned, but found that many others will swap in an A-body as well. Does anyone know if a box from a 98 blazer 4wd will work and what the ratio is?

[Schurkey]

You need to be as concerned with torsion bar thickness and angular motion as you are with the ratio of the gears.

The nice thing about the Jeep Grand Cherokee box is that it uses the "A" body steering motion (no internal steering stops) along with the second-stiffest torsion bar for better "feel".

You could, of course, have a custom box built with an even-stiffer torsion bar; but the price goes up dramatically.

Beware of commercially-rebuilt "Grand Cherokee" boxes that may not use the correct gear ratio or the correct torsion bar. The commercial rebuilt boxes DO NOT GUARANTEE that the internal parts are the same as what the vehicle came with originally.

Sorry, I can't help you with the Blazer box. I'm guessing that if it were a reasonable upgrade, we'd have already heard about someone making the swap.

[scott-462]

Just curious since my buddy has one he said he would give me. The "feel" is what i'm after cause one pinky turning isnt very sporty.

[Orion88]

I bought a remanufactured power steering box for an 85 Monte Carlo SS. Bolts right in, looks just like the stock unit, and has 2.75 turns lock to lock. It's one of the best and cheapest upgrades you can make on these old A bodies.

[1966Lemans]

Orion88, Any adapters needed for the hoses or rag joint?

[Orion88]

I'm not that far along in my restoration yet so I don't know from first hand experience, but the guys who told me about the swap, who I also bought my 70 GTO off of and who have been my mentors for my entire restoration process, said that it is a direct replacement with no adapters needed. They rebuild GTO's for a living and almost every single car they build they put this steering box on. I can at least tell you that when I had the Monte Carlo box sitting next to my GTO box they looked exactly the same. I can test fit my hose tonight if you like but I have not ordered a new rag joint yet. I'm almost certain no adapter will be needed but do your research.

[Nicks67GTO]

Do you have any reason that you're not just doing the tried and true JGC box swap? I did it on my 67' GTO. Its awesome and if you already have PS, the cost is under $100 bucks.

[Orion88]

I just went with what my mentors told me. They've been building GTOs for a while now. I'm just a punk college kid who grew up working in my dad's tool rental. It seems every time I don't take their advice I wind up screwing something up or creating more work for myself. I'm sure the JGC box works just fine. I don't know what they look like but being jeep/chrysler I would assume they look somewhat different than the gm a bodies? The monte Carlo box I know looks exactly the same. Might not fool a concours judge but to the average Joe, it looks OEM.

[1966Lemans]

One advantage to this swap is that the Monte Carlo SS box seems to be less expensive than the JGC box, when you look it up on various sites (NAPAonline, AdvanceAutoParts, SummitRacing, etc). It would be nice to know whether your hoses thread in, or whether they need an adapter. Some sites I looked seem to indicate metric threads, like the JGC.

--- Jay

[abefromen]

Everything you need for the JGC or MCSS swap you can get here although the rag joint is a lot cheaper at Rockauto. Lots of info here at PY just do a search for Jeep Cherokee or quick ratio gear box.

http://lee-powersteering.com/rebuild-misc.htm

Also if you buy a box from napa, autozone, etc it's hit or miss as to what box you really get. You're better off getting a box off CL or ebay that actually came off a JGC or Monte SS.

[abefromen]

Originally Posted by Orion88

I don't know what they look like but being jeep/chrysler I would assume they look somewhat different than the gm a bodies? .

Looks exactly the same.

[silverbullet07]

I would just have my correct one rebuilt with the quick ratio steering option added. That way you keep your original gearbox and you know it works with the car with no mods.

http://www.powersteering.com/ offers the option and has lifetime warranty on their rebuilds.

That's were I got mine. Super pleased with the result.

[Mr Twister]

Originally Posted by 1966Lemans

Orion88, Any adapters needed for the hoses or rag joint?

I did not see this posted above, so here goes.... I think there is a mid 80's Chevy truck Hybrid rag joint that has the right configuration. Hose adapters are also available (russell?) I put a rebuilt Grand National box on my metric Grand Prix and it was quite different. Go Kart like steering.

[Schurkey]

The Monte SS box has internal steering stops. Your turn radius is way larger than it should be.

[mrennie]

Originally Posted by 1966Lemans

Orion88, Any adapters needed for the hoses or rag joint?

I can answer that. I bought a used Monte Carlo SS steering box off a local guy here many years ago for $50, and a seal and bearing kit for $70 and rebuilt the box myself. LOTS of small ball bearings that need to be kept track of, but was a good challenge.

The hose connections are metric and a conversion rag joint is required. I bought some adapters at the local NAPA store that screw into the HP and return ports on the box, and allow the stock lines with SAE fittings to be retained.

The rag joint was from a late 70's GM truck, can't remember if it was 2WD or 4x4 but I have notes somewhere if someone really needs the info.

Seems the JGC is all the rage now but when I was looking for the low buck solution back then, the Monte Carlo or Grand National F41 boxes were the only known option.

One thing I forgot to do when I bought the box is take the pressure relief valve out out of the MC pump to put in my stock pump. The stock relief valve in a 70 GTO is set to around 950psi (IIRC) while the MC valve is more like 1200 or 1400 psi.

[mrennie]

Originally Posted by abefromen

Also if you buy a box from napa, autozone, etc it's hit or miss as to what box you really get. You're better off getting a box off CL or ebay that actually came off a JGC or Monte SS.

I agree with this 100%. Before I bought a used MC box I ordered a rebuilt box (twice) from the local NAPA dealer and neither were the 12.7:1 boxes, even though they were listed as being such.

Not sure about the JGC box, but a true 12.7:1 MC box has 2 small grooves (purely cosmetic) machined into the side of the worm shaft that the slower ratio boxes do not have. Unfortunately the only way to confirm this is remove the 4 bolt cover above the pitman shaft which requires removal of the preload nut, so if you are going to take apart a box to verify it is the real deal, you would need to reset the over centre preload which requires a beam or dial type inch pound torque wrench.

[scott-462]

Lots of info on here, but i've already read/seen it before about grand cherokee's and grand nationals, and MCSS, and a couple others. I need to know if a box from a 98 blazer 4wd is a bolt on and whats the ratio. A couple links lead me to believe it will bolt on, but has a ratio in the 14.5 range.. I'm not certain of this info though, hence the thread.