1998 C1500 Silverado: EVO delete: Pressure hose question

[L31MaxExpress]

From what I have read you do not need the 96 pump but a 96 gearbox. I believe @east302 said the same about one of his vehicles or again @sewlow had an adjustable fitting.

I know for a fact the gearbox is the same for all years for a given GVW. There is a boxed stamped 83 that has smaller internal pistons and one stamped 84 that has larger internal pistons. The heavier GVW vehicles got the 84 box. EVO vs Non-EVO did not change the gear box. Look at the 83 stamped box fitment, it was used from 88-2000. The 5/6 lug chassis got the 83 box and the 8-lug chassis the 84 box. I went from the 83 box to the 84 box about 6 months after rebuilding my 97 van. Noticed very little difference other than it felt like I had added a steering dampner to it. Less kickback on the wheel at highway speeds going over rougher roads. The larger piston absorbs more of the shock that is inputed into the box from the drag link.

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[df2x4]

EVO vs Non-EVO did not change the gear box.

This was my understanding as well. I don't think there's any need to change the gear box at all.

 

[df2x4]

Just double checked and RockAuto shows the same gear box part numbers for a '96 and a '97 C1500. There is no difference between them.

 

[L31MaxExpress]

This was my understanding as well. I don't think there's any need to change the gear box at all.

No need to change the box at all, but if you ever do, the 84 box is like adding an aftermaket steering dampner to the truck. The larger piston absorbs the nasty shock loads that are sometimes inputed into the steering system from the road. The 84 box would be great for oversize wheels and tires.

 

[A97obs]

Which is why I said grab the parts out of a junkyard pump. Technically you want all of these pieces out of a non-evo pump to properly delete the EVO. Personally I would want them out of a GMT400 so that the control valve provides the designed steering effort and feel for the earlier GMT400 truck. I can probably find the GM part numbers so you atleast have an interchange to go off.

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Ok so all 3 of these illustrated pieces are going to come out of a 88-96 gmt 400 pump weather a Silverado sierra yukon or suburban? And all 3 are removable once I remove the barrel nut ?
And then all 3 parts go back into the 99” pump after I take off the evo

It’s to technical at this point I’m not gonna go to a yard in the middle winter here and pull off a pulley which I would have to just remove the ps pump just to get to these pieces in the back . That much I do know ..

I’m assuming they’re not removable with out the pump pulled off the bracket ?

So if I can’t get them already outside of a pump as aftermarket replacements
I can just use the “over priced” Evo delete adapter with a 96 hose if I don’t want to go source a used pump right ?

 

[A97obs]

The spring is 05688037
The control valve is 07809221
The fitting is 26009894

EDIT- the spring is the same part number, so you already have the correct spring.

So you only need the control valve and fitting.

Both the control valve and fitting are discontinued from GM. Best bet is a 1980 through 1996 GM product with a steering gear box without hydroboost. These parts look consistently used even in stuff like a 1982 Caprice. Should be easy to get your hands on them. Basically I was correct when I said get the control valve and output fitting from anything GM that does not use hydroboost or a rack and pinon. Also FYI to make the hunt easier, Dodge trucks and vans through the 90s and into the early 2000s used them too.

Qualified genius thanks for being helpful

 

[98 Nitro]

Redhead lists the 1500 gearbox for the 97-99 as different part # than the 92-96.
I have both a 94 and a 98 GM also lists them as different but same housing, and a 3rd part # for 96.

 

[A97obs]

What’s this supposed to mean ? I’m lost
So do I not want to order and use a 96’ style line now on my 99 pump ?

 

[df2x4]

I can just use the “over priced” Evo delete adapter with a 96 hose if I don’t want to go source a used pump right ?

If you use the EVO delete kit you don't need the '96 pressure line. The EVO delete kit is designed to work with your existing '97+ pressure line, it just replaces the EVO solenoid on the back of the pump.

 

[A97obs]

If you use the EVO delete kit you don't need the '96 pressure line. The EVO delete kit is designed to work with your existing '97+ pressure line, it just replaces the EVO solenoid on the back of the pump.

I understand that , but i figured the 96 line swap was the best way , to avoid possible leaks with so many union's in that kit …coupled with the feedback I’ve seen on these evo deletes not holding up. So I was going for a more polished fix .
So your saying the delete kit is perfectly fine, it never offers anyone issues ?