Anyone swapped factory 20's for 18's on a NBS Silverado?

Discussion in 'Lifted & Offroad Suspension' started by phroadrick, Jul 14, 2010.

  1. phroadrick

    phroadrick New Member

    Hi all, I did a search and couldn't find this info anywhere. I have a 2008 Silverado extended cab with factory 20's and Goodyear LS 2 tires. This damn thing rides like a buckboard. I am thinking of swapping for a factory set of 18's that are a very similar style. The main reason being, I have driven a 2009 Silverado extended cab at work, identical to mine, that has the factory 18's and the difference in ride quality is night and day.

    My truck kicks very sharply over bumps and bad pavement and will beat you to death. I'm wondering if anyone else has done this or have you gone from 18's to 20's and noticed a decrease in ride quality?

    I know my gas mileage will also increase for two reasons. 1) the 18's have less rotational mass (weigh less). and 2) they have a smaller (narrower) tread width which will allow them to coast further when I lift off the gas pedal. I have driven MANY GM trucks and they all coast a long way after lifting off the gas. Not so with my 20's. When I lift off the gas on mine, it starts slowing immediately.

    I know some of you will think I am de-valuing my truck by removing the factory 20's and you are right to a point. If I were to trade it in the next 2-3 years, I would reduce my trade value by $800-$1000. However if I keep it 7-8 years or more, it really won't make a difference.

    The bottom line is I need to produce a better ride quality for everyday driving and this seems to be the easiest solution. It is also the cheapest, as it won't cost me a dime to swap.

    The tires on the 18's are 265, 65 18 Bridgestone Dueler A/T's.

    I welcome any and all comments and opinions. Oh, and I'm probably going to do this VERY soon, so please chime in!

    New truck.jpg

    18" rim
  2. phroadrick

    phroadrick New Member

    Bueller? Bueller?
  3. phroadrick

    phroadrick New Member

    47 views and not one response? Really?
  4. Pats1pab1

    Pats1pab1 New Member

    Wish I could help you out. I wonder if it has to do something with either the tires, brand, or shocks and suspension. I have a 99 Z with the Bridgestone Dueler A/T's and Bilstein Shocks and my truck rides smooth with some weight in the rear, but when the bed is empty it is rough and bumpy. I don't know what shocks they are putting on the trucks anymore. But the Z71 package is designed for off the highway use and makes the most use of suspension travel to keep the wheels on the ground when on the trail or dirt roads. So I really don't know if downsizing the rims will help.
  5. Are you running the factory recommended air pressures?
  6. Als09Sierra

    Als09Sierra New Member

    My Sierra has the same tires with the GMC chrome 20" rims, and my ride is very comfortable. My wife thinks it's one of the best rides for long trips that she's ridden in. I also have the Z85 performance/trailering suspension which may make a difference.
  7. Pats1pab1

    Pats1pab1 New Member

    Did find this. Z-71 package includes 46mm shocks, off-road jounce bumpers, stabilizer bars and skid plates, so it's going to be a much firmer suspension, and you'll feel that it's a little tighter and more rigid, while the Z-85 mainly consists of just 36mm piston monotube shocks, to enhance toungue weight and handling when the trailer is on the back. Handling with just the Z-85 will be about the same as the regular Silverado Classic.
    1 person likes this.
  8. Als09Sierra

    Als09Sierra New Member

    Thanks Paul. I had no idea what it meant other than that it is supposed to be a little smoother ride. I guess I need to find a boat to tow now. :happy:
  9. Pats1pab1

    Pats1pab1 New Member

    :lol:I need one too!! Maybe we can find a buy one get one free and go in on halves... all I get to tow is tools and trash to the dump!
  10. Als09Sierra

    Als09Sierra New Member

    LOL...I'm with you. Taking a dump run tomorrow.
  11. phroadrick

    phroadrick New Member

    I have the Z-85 suspension pkg and the tires are set to the factory recommended pressure of 30 psi.

    After much thought and deliberation, I've decided to keep the 20's. I'll keep my eyes open for a factory set of 18's and if I can pick them up inexpensively enough, I'll put them on and keep the 20's in the garage.

    Thanks everyone!
  12. Pats1pab1

    Pats1pab1 New Member

    Sorry, that we couldn't nail it down. I know when I have a little weight, tools in the bed, I get a smooth ride out of mine. When my bed is empty, I feel every bump and the ride is stiff. I just figured its because of the suspension being mainly for off road.
  13. Als09Sierra

    Als09Sierra New Member

    Glad to hear you're keeping the 20's. I'd be surprised if they're the cause. Maybe with 24's or 26's, but there's still plenty of sidewall on your tire. Could it be the conditions of the roads by you? I know the roads by me are pretty bad after the heavy snow from this winter. Pats1pab1 makes a good point too, add a little weight to the bed and see if that helps.
  14. 2010SSRS

    2010SSRS New Member

    if i may suggest.........keep ur 20x8.5 wheels, spend $70 and get the Rough Country 2" front end leveling kit then get some 275/60/20 or even 275/65/20 tires. the 275/60/20 are equivilent to the 275/65/18. you may be able to even get the 275/65/20 which will be smoother yet if you keep ur stock wheels because of the offset and width. it'll make ur ride smoother and look great too!

Share This Page