Help Me Choose Correct P/S Box

[Kawabuggy]

I'm working on a '70 C10 L/B truck. Just dropped a built 5.3LS engine with 4L60E trans into the truck the past 2 days. Truck came factory with manual steering. Since the LS motor I dropped in already has the power steering pump present, I want to upgrade the steering box to power assist.

Can anyone share with me from what year truck I can find a direct bolt in box that uses the same hose fittings as the current P/S pump has on it? Any other tips, or tricks I should be aware of regarding getting the P/S pump and new steering box to play well together?

I'm loving working on this truck already. So much room under the hood. The engine looks tiny sitting down in there! I can stand on 3 sides of the engine in the bay with my feet on the ground!

Thanks in advance for any help!

[Kawabuggy]

Okay, I did a bunch of reading last night and have figured out that the fittings on the steering box, and/or the pump, are easily worked around.

Next, better, question.. Which power steering box has the fewest # of turns lock-to-lock, with the best "feel"?

[Getter-Done]

The link below is the one a lot of people talk about on here.
It a little higher that your normal options.
https://www.redheadsteeringgears.com/

[Kawabuggy]

Looks like a very nice product but WAY over my budget. I suspect I can get the entire power steering project done for less than half the price of one of those boxes alone.

Does anyone know the specs on later steering boxes? I need something that has better "feel" and fewer turns lock-to-lock. I'm reading that the 1978+ boxes will have the metric fittings that will work with my current power steering hose connection, and will have 3.5 turns L-T-L..

[AussieinNC]

78 on power boxes are a better feeling box than the earlier ones...and yes...3.5 turns ltl...and metric style fittings.

Make sure the chassis has the clearance dimple where the box mounts ....being a "70" is should have it, even though it was a manual box from factory....

but I have seen 67's masquerading as later models...

What power assist are you using on the brakes?

Hydroboost is an easy conversion and will work fine with the current LS pump.

[Kawabuggy]

It has a vacuum cannister for the brakes now. I have already purchased a front disc brake conversion kit and it is coming. After the front discs, I'm leaving the brakes alone.

I'm going to go ahead and purchase a 1978+ P/S box and get it installed. Thanks for the information!

[dell72]

I installed a steering box from an 87 C-10 in my 69 C-10. The 87 box has a nice road feel and much faster ratio than the old manual box.

[Willys_MB]

Originally Posted by dell72

I installed a steering box from an 87 C-10 in my 69 C-10. The 87 box has a nice road feel and much faster ratio than the old manual box.

Is that a direct bolt in? I'm looking at adding P/S pretty soon here and I'm trying to figure out the best route as well.

[Kawabuggy]

Dell, thanks for the information! I was wondering what the final year was that Chevy stopped putting the steering box on the OUTSIDE of the frame rail and moved it to the INSIDE. I mentioned in another post that I recently drove a 2000 Silvy 4x4 that had a P/S box and LOVED the road feel, and turning radius.. But, when I started doing research on that particular vehicle I found that the P/S box had moved to the INSIDE of the frame rail in that year. Now I know, thanks to your post, that in 87 they were still on the outside.

Now I have an idea that I'd like to throw out there.... I used to have a '69 Camaro and the hot thing to do with them was to take a 1988 Iroc Z-28 steering box and put it in that car. It gave remarkable road feel, and a very short 3 turn lock to lock... Would it be possible to remove the guts from one of those Z-28 boxes, and put the internals into a "truck" box? I guess the only thing that would worry me would be if the pittman arm is splined the same way, or not... Inquiring minds want to know if it can be done..

[AussieinNC]

Along with the conversion to disk fronts...make sure you get the correct master cylinder to run the disks front and drums rear...

Also make sure you use the correct brake bias valve...

And new brake pipes I assume?

On that LS engine, where are you pulling engine vacuum from for the booster?

Most folk with a built LS...aka lumpy cam, low vacuum at idle etc....swap over the hydro boost systems and run them from the power steer systems...

[68c10airstream]

Originally Posted by Kawabuggy

Dell, thanks for the information! I was wondering what the final year was that Chevy stopped putting the steering box on the OUTSIDE of the frame rail and moved it to the INSIDE. I mentioned in another post that I recently drove a 2000 Silvy 4x4 that had a P/S box and LOVED the road feel, and turning radius.. But, when I started doing research on that particular vehicle I found that the P/S box had moved to the INSIDE of the frame rail in that year. Now I know, thanks to your post, that in 87 they were still on the outside.

Now I have an idea that I'd like to throw out there.... I used to have a '69 Camaro and the hot thing to do with them was to take a 1988 Iroc Z-28 steering box and put it in that car. It gave remarkable road feel, and a very short 3 turn lock to lock... Would it be possible to remove the guts from one of those Z-28 boxes, and put the internals into a "truck" box? I guess the only thing that would worry me would be if the pittman arm is splined the same way, or not... Inquiring minds want to know if it can be done..

Stick with the 78 and newer box from a c10. You should end up with a 3 1/2 turns lock to lock and variable ratio (my favorite box). You would end up with metric o'ring style hoses needed for the box and pump. If you do a ls hydroboost change over as i did on my 68 c10, the pump reservoir tank for hydroboost has an additional return nipple on it, and the screw in fitting and valve in the back of the pump is different in a hydroboost application with a bigger hole for more volume.

[Kawabuggy]

Okay, just to follow up with what I ended up doing.. I bought a remanufactured P/S box for a 1985 Chevrolet Silverado. It DOES bolt right in. Then, I realized that the rag joint, or rubber isolator mount that goes between end of steering column, and P/S box-is DIFFERENT. No problem-XL parts had the correct rag joint ($69-OUCH!) and that allowed everything to bolt together correctly. Then, for the power steering line we used-wait for it...


The pressure hose for a 1985 Chevrolet Silverado! Using this pressure hose does require cutting a hole in the inner fender. The inner fender is directly on top of the threaded ports on the box. We literally used a step type bit to keep gradually opening up the hole until the line fit through the hole, and lined up with the box. The end of this line is straight so the hose sticks straight up through the hole in the inner fender. The line is the perfect length though. Everything was a direct bolt in with no fabrication (other than cutting the hole in the inner fender).

Miracle but NO LEAKS. Has to be the first time I've done anything with a P/S system and did not have leaks after the fact.

[67 chevelle]

Ill 3rd the 78 box , its whats in my 68 , it had ram assist when i got it , what a mess that was , the 78 box is great , put a sway bar up there if it does not have one