[JJam]

I just bought some 20" Momo wheels and they have toyo 305/50R20 tires. I bought them used I took them and had them balanced just in case. When I brake the front end shakes bad, the stock wheels were fine. I have a 06 Silverado crew cab if it makes a dif. Are the tires too big/wide?

 

[Crawdaddy]

The rotors could be warped. I would think that if you put larger tires on, the larger mass could make it more noticable.

 

[JJam]

on a new truck, the stock wheel had/showed no problems?? if so I'll take it back to the dealer. I only have $600 in the wheels

 

[unplugged]

Increasing the tire diameter by more than 3% is dangerous because it overloads the brakes and can cause brake failure. Just because everyone does it, doesn't make it right. As you can see by the comparison chart, you at over the safe limit as far as tire size.

From: 1010tires.com

Stock Tire - 245/70R17..................... .....Tire 1 - 305/50R20
Section Width:9.64 in245 mm...........Section Width:12.00 in305 mmRim
Diameter:17 in431.8 mmRim.............Diameter:20 in508 mmRim
Width Range:6.5 - 8 inRim.................Width Range:8.5 - 11 in
Overall Diameter:30.50 in774.7 mm....Overall Diameter:32.00 in812.8 mm
Sidewall Height:6.75 in171.45 mm......Sidewall Height:6.00 in152.4 mm
Radius:15.25 in387.35 mm..................Radius:16.00 in406.4 mm
Circumference:95.81 in2433.5 mm...........Circumference:100.5 in2552.7 mm
Revs per Mile:681.9..............................Revs per Mile:650
Actual Speed:60 mph........................100 km/h
Speedometer1:57.1 mph....................95.3 km/h
Speedometer Difference: -.....................Speedometer Difference: 4.907% too slow
Diameter Difference: -Diameter Difference: 4.69%

 

[JJam]

So should I go with 275/60-20, stock size option on the new silverado's? And will this fix my problem? I don't want to buy new tires and find out it was not the tires at all.

 

[unplugged]

I don't think I can accurately diagnose your problem all the way from the Mojave Desert. I am just trying to help you find the solution to your particular problem. Do you have the original wheels and tires that you can put back on to test with?

 

[JJam]

Just put the stock wheels back on the truck, I'll take it to work 2morrow and let you know the outcome.

 

[TahoeFever]

bigger wheels means upgrading the brake system also

 

[dwill3015]

Is your 06 Crew Cab a 1500, or a 2500? I run the same size on my 06 2500HD with no probs at all. I have 305/50/R20 Toyo Open Country A/T's on Ultra wheels.

I have a much easier time braking with my truck that my Wife does with the same tires only in 18" on her 1500 Suburban because of the brake size difference.

 

[JJam]

well went to work and no braking problems, no shake. So when you get 20" from the dealer they are not upgrading the brakes. So I'm thinking with the 20" rims you need to run the smaller tires, which is what they have on the stock 20" rims (275/60-20 tires with a rim 20x8.5) Thanks everyone with this problem, hope it will help others.

 

[dwill3015]

Bought my truck new from the dealer with 20's. Is your truck a 1500, or a 2500??? That could be making the difference in brake size.

 

[JJam]

1500 the stock/oem are 17"

 

[unplugged]

Is your 06 Crew Cab a 1500, or a 2500? I run the same size on my 06 2500HD with no probs at all. I have 305/50/R20 Toyo Open Country A/T's on Ultra wheels.
I have a much easier time braking with my truck that my Wife does with the same tires only in 18" on her 1500 Suburban because of the brake size difference.

The brakes on the 2500HD are awesome. I have never had better brakes on any truck. I have 88k+ miles on my 06 with the original pads. Had it serviced last week and the pads still are at 75%.arty:

 

[dwill3015]

The brakes on the 2500HD are awesome. I have never had better brakes on any truck. I have 88k+ miles on my 06 with the original pads. Had it serviced last week and the pads still are at 75%.arty:

Now that's what I'm talking about!arty: It's awesome how well mine stops even with the extra weight of the Duramax diesel:great:

 

[dwill3015]

1500 the stock/oem are 17"

I think that's the problem but maybe someone else in this community that runs oversized wheels on a 1500 might have some suggestions as to how fix your prob so you can skate on 20's. I would like to see some pics of your ride if you could post some.:great:

 

[JayMack75]

Sometimes its a necessary evil if you want to go big. Thats why people always complain about oversized wheels vs. sacrifice of ride I believe. Mine shakes very little under braking, but thats primarily because of varying ride height.

 

[JJam]

this is how she looked with the wheels, now off in the G-rage

 

[Paul M]

The real reason for the 17" wheels was to accept the large disc brake rotors on cars. The purpose for 18, 19, and 20-22" wheels to me is not clear. I suppose they need to be larger for trucks but most have small rotors sitting in large wheels. They may also be trying to keep the overall OD the same to not affect the speedometer. Whatever the case, your vehicle will perform the best with the wheel/tire combination your vehicle was designed for.
You probably have a little rotor warpage not noticeable with stock wheels and tires. Well here you go. Screw with the engineering and it is not going to work well. Automotive design has been optimized to save weight and fuel. Mess with it and you could be in trouble.

 

[JJam]

well came back from the Dealer and they said they did not feel andy shake, I told them with the stock wheels it was not notice. I told them when I put on the other wheels that is when I notice the warpage. They said well "Sorry if it did not come stock on the truck it is not covered in the warranty. :rules: So the way it looks if I want to run the other wheels I would need to pay for turning the rotors myself. I think I'll see about turning them and see. Just like I need more to do on the weekend.