Switching 20" wheels to 18" wheels - Chevy Impala Forums
Chevy Impala 9th Gen Discussion Epsilon II 2014+. Discuss all Chevy Impala 9th Generation Performance and Technical Discussion here.

User Tag List

 3Likes
  • 1 Post By Bowtie396
  • 1 Post By Bowtie396
  • 1 Post By ICUBB
 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 5 Days Ago Thread Starter
Junior Member
 
tforkner's Avatar
 
Join Date: Jun 2019
Posts: 5
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Switching 20" wheels to 18" wheels

I have an '18 Impala Premier with the 20" wheels. I had the misfortune of bending two of them when I hit a pothole in Indiana. Repairs done at the local stealership were unsatisfactory. I am considering buying four new 18" stock wheels and 245/50 r18 tires which are really close to the same diameter and width of the 20" stock setup. I'll keep the twenties and tires in case I ever want to trade the car in. I figure the 18" wheel/tire combo will give me some sidewall flex the 20s don't have, as well as replacing the damaged/straightened wheels.


My questions: Will this wheel/tire combo clear the struts at the top and fit well around the brakes? Can the pressure sensors be switched from the old tires to the new? I had that done on another car I had with no problem.
tforkner is online now  
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 2 Days Ago
Senior Member
 
USN24's Avatar
 
Join Date: Feb 2019
Location: Tennessee
Posts: 127
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 29 Post(s)
Thanks: 56
Thanked 14 Times in 14 Posts
Garage
That must have been one gigantic pothole. As for answering your questions, sorry I have no idea but would start by comparing part numbers for the premier vs the LT with the 18 inch stock wheels. Good luck and maybe some others on the forum can provide more information.



Anything worth doing is worth doing right!

Ed
USN24 is offline  
post #3 of (permalink) Old 2 Days Ago
Senior Member
 
Bowtie396's Avatar
 
Join Date: Apr 2018
Posts: 102
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Thanks: 0
Thanked 5 Times in 4 Posts
The 18" wheels will fit as the Impala LS already uses them. Struts, Brake Rotors & Calipers are the same across the board on all models of the Impala. Pressure sensors can be moved to the 18" wheels.
sheila likes this.
Bowtie396 is offline  
Sponsored Links
Advertisement
 
Junior Member
 
C6Lee's Avatar
 
Join Date: Sep 2016
Posts: 12
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
I've got a set of the same wheels, 20's if you are ever interested in them, have 5000 miles. Got a new chrome set. Would sell the entire set for a great deal...
C6Lee is offline  
Senior Member
 
Joes74challenger's Avatar
 
Join Date: Apr 2016
Location: Fort Wayne
Posts: 1,293
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 253 Post(s)
Thanks: 30
Thanked 122 Times in 118 Posts
Garage
i know on the police calipers when they were upgrading brakes on 8th gens it would say "17" on the caliper itself indicating it needed at least a 17 inch rim to clear the brakes. i would pull a wheel and look for such a marking before buying a different set of rims.
Joes74challenger is offline  
Senior Member
 
Bowtie396's Avatar
 
Join Date: Apr 2018
Posts: 102
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 40 Post(s)
Thanks: 0
Thanked 5 Times in 4 Posts
Quote:
Originally Posted by Joes74challenger View Post
i know on the police calipers when they were upgrading brakes on 8th gens it would say "17" on the caliper itself indicating it needed at least a 17 inch rim to clear the brakes. i would pull a wheel and look for such a marking before buying a different set of rims.
There is no police version of the current Impala. The calipers are the same no matter what trim level. The car comes from the factory with 18" wheels. The Rotors, Calipers & Suspension are the same weather it's a LS, LT, LTZ or Premier.

I would get Factory 18" wheels if you can.
sheila likes this.
Bowtie396 is offline  
Member
 
RobHazmat's Avatar
 
Join Date: Mar 2019
Posts: 86
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 27 Post(s)
Thanks: 0
Thanked 8 Times in 8 Posts
Quote:
Originally Posted by Joes74challenger View Post
i know on the police calipers when they were upgrading brakes on 8th gens it would say "17" on the caliper itself indicating it needed at least a 17 inch rim to clear the brakes. i would pull a wheel and look for such a marking before buying a different set of rims.
As bowtie has already stated, all brake and suspension components are the same across the board for all trims. All you need to do is swap the rims and make sure the tire size is correct.
RobHazmat is online now  
Junior Member
 
rasmaxwell's Avatar
 
Join Date: Aug 2019
Location: Ohio
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by tforkner View Post
I have an '18 Impala Premier with the 20" wheels. I had the misfortune of bending two of them when I hit a pothole in Indiana. Repairs done at the local stealership were unsatisfactory. I am considering buying four new 18" stock wheels and 245/50 r18 tires which are really close to the same diameter and width of the 20" stock setup. I'll keep the twenties and tires in case I ever want to trade the car in. I figure the 18" wheel/tire combo will give me some sidewall flex the 20s don't have, as well as replacing the damaged/straightened wheels.


My questions: Will this wheel/tire combo clear the struts at the top and fit well around the brakes? Can the pressure sensors be switched from the old tires to the new? I had that done on another car I had with no problem.
I switched out the 20" wheels for 18" wheels when I took delivery of my 2019 Impala earlier this year. No issues. No regrets.
rasmaxwell is offline  
post #9 of (permalink) Old 11 Hours Ago
Senior Member
 
ICUBB's Avatar
 
Join Date: Feb 2016
Location: NJ, USA
Posts: 475
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 109 Post(s)
Thanks: 93
Thanked 86 Times in 80 Posts
Garage
Quote:
Originally Posted by tforkner View Post
I am considering buying four new 18" stock wheels and 245/50 r18 tires.
Tirerack lists the proper size for the 18 Impala as 235/50-18. Anything over sized is a risk you would have to assume. Probably not going to find the proper answer here.

Here is the sizing info from Tiresize.com as a comparison of 235 vs 245.

Diameter
27.3" 235
27.6" 245
+1.1%

Width
9.3" 235
9.6" 245
+3.2%

Sidewall
4.6" 235
4.8" 245
+4.3%

Circum.
85.6" 235
86.8" 245
+1.1%

Revs/Mile
740 235
730 245
-10
plano-doug likes this.

https://www.impalaforums.com/signaturepics/sigpic129377_1.gif
Just a resident noob.
ICUBB is offline  
post #10 of (permalink) Old 9 Hours Ago
Junior Member
 
Pat Currie's Avatar
 
Join Date: Aug 2019
Location: Phoenix, AZ
Posts: 20
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Thanks: 4
Thanked 0 Times in 0 Posts
Best O Luck! Let us all know how much better the ride is after the 18s are installed. Thanks!
Pat Currie is offline  
post #11 of (permalink) Old 2 Hours Ago Thread Starter
Junior Member
 
tforkner's Avatar
 
Join Date: Jun 2019
Posts: 5
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
ICUBB, the reason I suggested 245/50 r18 tires is that they nearly match the circumference and width of the 20" tires they'll be replacing. That will leave speedometer error at a minimum. 245/40 r20: circumference 87", diameter 27.7", width 9.6" For the 245/50 r18s, circumference 86.8" (two extra revolutions per mile), diameter 26.7", width 9.6". There is no doubt the stock twenties leave no room for anything bigger (there may be 1/4" gap between the tire and the strut), but these are the same width with a bit smaller diameter and circumference.


Thanks to everyone for the replies!
tforkner is online now  
post #12 of (permalink) Old 2 Hours Ago
Senior Member
 
1954 Chevy's Avatar
 
Join Date: Jun 2014
Location: central KY
Posts: 277
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Thanks: 7
Thanked 41 Times in 32 Posts
Garage
Quote:
Originally Posted by C6Lee View Post
I've got a set of the same wheels, 20's if you are ever interested in them, have 5000 miles. Got a new chrome set. Would sell the entire set for a great deal...
What state are you located in?
1954 Chevy is offline  
Sponsored Links
Advertisement
 
Reply


Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevy Impala Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in













Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome