Steering Box Differences (88-98)

[mr98z71]

So after having removed the EVO Fitting on the back of my 98 K1500 power steering pump, i found that my steering is way too easy to steer on the highway. After doing some research, I was told to swap my gear box with one out of a 98. I also found that the P# for the 96 trucks were only used for that year, one part number for 88-95 and another for 97-98. Id like to know if there is any differences from 88-95 and 96 wether it be ratio or what not.

any input would be much appreciated!

 

[Jrgunn5150]

So after having removed the EVO Fitting on the back of my 98 K1500 power steering pump, i found that my steering is way too easy to steer on the highway. After doing some research, I was told to swap my gear box with one out of a 98. I also found that the P# for the 96 trucks were only used for that year, one part number for 88-95 and another for 97-98. Id like to know if there is any differences from 88-95 and 96 wether it be ratio or what not.

any input would be much appreciated!

The EVO is the difference, but there's a bypass kit for 60 bucks that's even easier and will make it steer normal.

 

[mr98z71]

I Need to know why the 96 trucks used a different box then the 88-95. Evo came out in 97

 

[Jrgunn5150]

96 is a Vortec, different lines than a TBI, then 97-97 are EVO.

you can even take the non-EVO orifice from a 96 box and put it in an EVO box.

 

[mr98z71]

From what Ive read, 88-98 steering gear boxes are interchangeble but there is 3 different models used at least throughout the years. I need to know the internal differences between them like ratios and whatnot.

 

[Supercharged111]

My understanding was that the difference was HD vs. non. I simply unplugged the steering column sensor inside my 98 as it was throwing a code and making the EVO do its usual BS. Truck has since felt normal, but I will say it's lighter than the steering in my 97 dually with stock 225s. It doesn't feel wrong by any means, if your truck lacks steering feel you may be due for an alignment. When I cranked my truck and put on 285s I lost all feel but it returned once I gave it an alignment.

 

[df2x4]

I simply unplugged the steering column sensor inside my 98 as it was throwing a code and making the EVO do its usual BS. Truck has since felt normal, but I will say it's lighter than the steering in my 97 dually with stock 225s.

I'm surprised you don't notice a bigger difference with the EVO at full boost. In my experience it's a night and day difference when that speed sensor on the column goes out. My red truck is parked right now until I can replace the sensor (again), I don't like driving it over 40 or so with the EVO pumping full blast. Steering is way too easy.

 

[Jesse_Wenting]

In case the OP is still looking for an actual answer, the difference is in the input shaft, but there's only 2 styles at least now.

While both styles use a 18.42mm input shaft diameter, 88-96 had 35 splines whereas 97-98 (probably the classic 1500s and 3500s up to 02 but not positive) only had 25 splines, and obviously the addition of EVO

 

[GoToGuy]

When my mom and dad bought new 95 K2500 xcab sb, what a great truck. In 98 my mom decided she wanted a suburban one day. I get a call one day, " ccome over for dinner" . And there's a brand new 4x4 Sub'. The difference in steering feel between the two is night and day. The truck a guy can steer with one finger most likely a women could not it just has higher resistance. The suburban I can steer with my little finger, it is way less resistance. A few years later at UAL I mentioned that to coworker, former Chevy dealer tech, said " from feedback from soccer moms complaint's about heavy hard turning, they made some pump, steering related changes". Made perfect sense to me. I never dug into it, just look around Tahoe, Escalade, Sub's. Would i bet my life on it? Nope, i know how to do the research if i need to.

 

[Vikingdude]

When you unplug a component of the EVO system, it reverts to full boost at all times. Some folks report this is also hard on the system and can prematurely blow seals. GM has a kit that installs on the back of the pump that replaces the EVO and has a tuned oriface size that stiffens the steering up a good amount. You have to remove the pump to install it, so consider just replacing it with one of the "Evo delete" pumps that are available