Before I took the C2500 Suburban (2WD) on a long trip, I had the front end rebuilt with new control arms and ball joints. Steering was OK at lower speeds. At highway speeds, the vehicle would oversteer to the left or right with very little input on my part. It was terrifying to drive. I exited the highway and looked everything over and decided to try lowering the tire pressure on the front tires. (C2500 with 80 psi tires) I lowered the front to 40 psi and it helped a lot. It still was a monster with wind gusts, crosswinds, and semi trucks.
My 1996 C1500 suburban was rock solid on the highway and was a joy to drive!
What I found out was this was related to the EVO steering system that used speed and steering wheel inputs to control the pressure to the steering system.
1. I disconnected the Steering Wheel Motion Sensor as it was sending erratic signals to the system. This helped, but it still was too easy to steer.
2. I replaced all steering linkages with new parts.
3. I installed the GM EVO delete kit (19168825) to bypass the EVO solenoid on the rear of the power steering pump. This helped, but it still was too easy to steer.
4. I then added the 916-68001 Power Steering Flow Valve Kit. I added 3 of the 5 washers to lower the power steering pump flow. This helped a lot, but I am still not satisfied with the results. I plan on adding the last two washers to see if it helps.
Anyone have some ideas that I missed? Maybe some Rancho Steering Stabilizers?
It is now 2020 and I still need a total solution for this.
A D V E R T I S E M E N T S
Before I took the C2500 Suburban (2WD) on a long trip, I had the front end rebuilt with new control arms and ball joints. Steering was OK at lower speeds. At highway speeds, the vehicle would oversteer to the left or right with very little input on my part. It was terrifying to drive. I exited the highway and looked everything over and decided to try lowering the tire pressure on the front tires. (C2500 with 80 psi tires) I lowered the front to 40 psi and it helped a lot. It still was a monster with wind gusts, crosswinds, and semi trucks.
My 1996 C1500 suburban was rock solid on the highway and was a joy to drive!
What I found out was this was related to the EVO steering system that used speed and steering wheel inputs to control the pressure to the steering system.
1. I disconnected the Steering Wheel Motion Sensor as it was sending erratic signals to the system. This helped, but it still was too easy to steer.
2. I replaced all steering linkages with new parts.
3. I installed the GM EVO delete kit (19168825) to bypass the EVO solenoid on the rear of the power steering pump. This helped, but it still was too easy to steer.
4. I then added the 916-68001 Power Steering Flow Valve Kit. I added 3 of the 5 washers to lower the power steering pump flow. This helped a lot, but I am still not satisfied with the results. I plan on adding the last two washers to see if it helps.
Anyone have some ideas that I missed? Maybe some Rancho Steering Stabilizers?
It is now 2020 and I still need a total solution for this.
- Joe C., McKinney, US