'07 Classic W/z71 - Improve Handling

[Offshore24]

How do I best improve the rdie and handling of my '07 Silverado Classic, ext cab, w/Z71?

 

I expected a firm ride with decent handling when I bought this truck. It wallows and bump steers and generally is too soft. I picked it up used with 23,000 miles on it. Should I try new shocks? Is this just a typical Classic suspension ride issue?

 

I've also noticed the steering column rattle that has been discussed on other topics.

[jrrod2004]

you riding on the Bridgestone Duelers? They make for a decent tire when doing light off roading but they are not very good for a smooth ride when on regular streets (unless the street is perfect). I would throw on a set of tires that are not really designed for off road and get the I-Shaft replaced. The front suspension on the Z71 is usually torsion bar so it is not the best for improving ride (vs. coils)

[Offshore24]

OEM goodyears

[2007VictoryRed]

I changed my shocks around 25k to bilstein. It made a little differnce. But like said befor get better tires. Maybe P rated tires.

[Stevens03]

Shocks might help, but changing to a performance tire, and lowering the truck 2-3" will make a big difference

[Spurshot]

OS24,

The "wallowing" and the bouncing "bobblehead" effect can be fixed with some good shocks. My 99 2500 needed shocks shortly after I bought it new, probably about the mileage you have. My 08 needed front shocks right away as the OEMs were worthless. I just changed the 08 4x4 1500 fronts to Bilstein 5100 series and it's a vast improvement.

 

"bump steering" is a function of steering geometry and suspension integration of design. Bump steering is when the steering angle changes as the suspension is compressed or extended. Severe bump steering is due to poor design. Most people think bump steering is when something hits the tire and physically, directly, deflects the angle of the wheels. A steering stabilizer might help the latter condition.

 

If it's a 4x4 that gets used for off-road at all, I wouldn't lower it, even though that would reduce body roll if done correctly.

 

Depending on how the truck handles, a larger front or addition of a rear swaybar could be helpful to control body lean in corners and abrupt manuevers. I think Helwig makes aftermarket swaybars for trucks as well.

 

I'd start with the decision on lower or not to lower. That determines your basic spring package. Then get shocks with the damping rates you want. From there, you can check for body roll and understeer/oversteer and decide if you need different sway bars.

 

On the shocks, I think either the standard Bilsteins or the 5100 series Bilsteins would work well for you if you're looking for a normal useage. Some of the others around here have used the KYBs and other major brands to good result. I'm just a fan of Bilstein because I've had good results with them.

 

There's no doubt about having a good street tire perform better than A/T type tires when on pavement. Tires could be a huge difference. I've recently come back to the new Goodyear Eagle GT for my wife's Infinity I30. Nice performance tire.

 

But I'd set up the suspension first, especially if it's a 4x4, since a good street tire is about as good as a slick in the dirt.

[jrrod2004]

OS24,

The "wallowing" and the bouncing "bobblehead" effect can be fixed with some good shocks. My 99 2500 needed shocks shortly after I bought it new, probably about the mileage you have. My 08 needed front shocks right away as the OEMs were worthless. I just changed the 08 4x4 1500 fronts to Bilstein 5100 series and it's a vast improvement.

 

"bump steering" is a function of steering geometry and suspension integration of design. Bump steering is when the steering angle changes as the suspension is compressed or extended. Severe bump steering is due to poor design. Most people think bump steering is when something hits the tire and physically, directly, deflects the angle of the wheels. A steering stabilizer might help the latter condition.

 

If it's a 4x4 that gets used for off-road at all, I wouldn't lower it, even though that would reduce body roll if done correctly.

 

Depending on how the truck handles, a larger front or addition of a rear swaybar could be helpful to control body lean in corners and abrupt manuevers. I think Helwig makes aftermarket swaybars for trucks as well.

 

I'd start with the decision on lower or not to lower. That determines your basic spring package. Then get shocks with the damping rates you want. From there, you can check for body roll and understeer/oversteer and decide if you need different sway bars.

 

On the shocks, I think either the standard Bilsteins or the 5100 series Bilsteins would work well for you if you're looking for a normal useage. Some of the others around here have used the KYBs and other major brands to good result. I'm just a fan of Bilstein because I've had good results with them.

 

There's no doubt about having a good street tire perform better than A/T type tires when on pavement. Tires could be a huge difference. I've recently come back to the new Goodyear Eagle GT for my wife's Infinity I30. Nice performance tire.

 

But I'd set up the suspension first, especially if it's a 4x4, since a good street tire is about as good as a slick in the dirt.

 

 

See, we have real experts here

[WilliamBos]

The addition of a rear sway bar helps alot?? Stock rubber on mine we be getting replaced next year, crappy P rated LTX will be going in favour of LT tires - NOT Michelins.

 

Is the factory front bar OK??

[Spurshot]

The addition of a rear sway bar helps alot?? Stock rubber on mine we be getting replaced next year, crappy P rated LTX will be going in favour of LT tires - NOT Michelins.

 

Is the factory front bar OK??

 

 

When I recall setting up a SCCA car back in the seventies, in general terms, if you increased the front roll stiffness, you usually increased the understeer...when you increased the rear roll stiffness, you increased the oversteer. So, back to "Is the factory front bar OK??". OK? Yes. Optimized? More likely a compromize of all around loading handling and ride. Besides, there are more than one front sway bars for most years of Silverados. I think the 2008 1500 had 3 different diameters available in various pkgs. I'd look into which bar you have and decide if you want to change it to a larger factory bar or go with the aftermarket options. At least one member here has the Hellwig bars front and rear and thought they were great.

 

With a pickup, you have to deal with large loading configuration differences so you probably want to chose a loading configuration to target your performance requirements to. Tuning up the handling of a truck with only the driver in it may not be what the goal is for some. Some may want to have the handling optimized for their trip configuration, be that all their hunting gear or a topper and 3 Sea Chests of ice and beer. You may also want to know if you simply want to improve the "normal" manuevering performance vs. the cornering limits.

[jrrod2004]

The addition of a rear sway bar helps alot?? Stock rubber on mine we be getting replaced next year, crappy P rated LTX will be going in favour of LT tires - NOT Michelins.

 

Is the factory front bar OK??

 

 

When I recall setting up a SCCA car back in the seventies, in general terms, if you increased the front roll stiffness, you usually increased the understeer...when you increased the rear roll stiffness, you increased the oversteer. So, back to "Is the factory front bar OK??". OK? Yes. Optimized? More likely a compromize of all around loading handling and ride. Besides, there are more than one front sway bars for most years of Silverados. I think the 2008 1500 had 3 different diameters available in various pkgs. I'd look into which bar you have and decide if you want to change it to a larger factory bar or go with the aftermarket options. At least one member here has the Hellwig bars front and rear and thought they were great.

 

With a pickup, you have to deal with large loading configuration differences so you probably want to chose a loading configuration to target your performance requirements to. Tuning up the handling of a truck with only the driver in it may not be what the goal is for some. Some may want to have the handling optimized for their trip configuration, be that all their hunting gear or a topper and 3 Sea Chests of ice and beer. You may also want to know if you simply want to improve the "normal" manuevering performance vs. the cornering limits.

 

 

 

and I thought it was simply bolting on the Hellwigs and getting better cornering abilities...

[rogerf]

How do I best improve the rdie and handling of my '07 Silverado Classic, ext cab, w/Z71?

Replacing shocks made a world of difference on handling for my old truck ('97 1500 w/t). Also front sway links and D-blocks were replaced at the same time with urethane bushings. If I had to do over, would have added a sway bar to the rear suspension. It's important for handling to keep tires inflated to max pressures with "P" rated tires. Eventually bought a pair of Bridgestone A/T's for the rear for winter that were LT rated. Handling improved so much on the LT rated tires I left them on all the time.

[Spurshot]

... Also front sway links and D-blocks were replaced at the same time with urethane bushings. ... It's important for handling to keep tires inflated to max pressures with "P" rated tires....

 

 

Great catch on the sway bar bushings. They increase the instantaneous spring rate of the sway bar (make it stiffer for the short throw) and reduce total body roll as well. The tire pressures for hard cornering are usually much higher than normal driving. On a truck where weight distribution is high in the front, tire pressures should be higher in the front by a significant amount and adjusted to get the handling you want. All this, of course, does not consider tire wear.

[Offshore24]

Thanks for the input guys.

 

I had a F150 before. First thing I did with that was put Rancho 9000 adjustables in it. Fixed the ride and handling right to where I liked it. The Ford also had torsion springs in the front. Bilsteins on a truck I have no experience with. I've read here that they are very poplular with you guys. Will have to consider that as my first upgrade. Tires are too $$ to just replace before I wear these out. So that will have to wait. My experience with poly bushing upgrades is they cause the ride to become harsh and the steering wheel feedback to become harsh too. Anyone have a classic silverado with poly bushing upgrade?

[lerbud]

I would start with tire pressure first. You will be amazed how much better your truck will ride with lower pressure. Start with 34 in front and 30-32 in the back. That will fix a lot of the handling issues. Then you can decide if you need shocks etc. Be sure to adjust air pressure early in the morning before driving. Mine jumps all over the road when the pressure is too high.

[Offshore24]

I would start with tire pressure first. You will be amazed how much better your truck will ride with lower pressure. Start with 34 in front and 30-32 in the back. That will fix a lot of the handling issues. Then you can decide if you need shocks etc. Be sure to adjust air pressure early in the morning before driving. Mine jumps all over the road when the pressure is too high.

 

I'm running 34 at both ends. I tried higher pressures when the truck was empty to see what would happen and that didn't work out. I'll try dropping the back a couple of pounds and see what happens. thanks.