Backspacing question - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**CC69Rat** · 06-07-2012, 08:54 PM

Realizing most people (with 20's) run 20x8.5 up front with 5.25" Backspacing .. 255/40/20

4.5" drop seems to be the norm. I am about to drop my GMC and that's around where I'll be too.

I want just a touch more sidewall up front. I have 255/45/20's ready to go. I am about to buy my wheels and I'm down to two. The issue is the ones I really want only come in 20x8 with 4.5" Backspacing.

So .. in theory if it were an 8.5" wheel instead it would be the same as 5" Backspacing. Just shove that extra width to the back. ..

However: 20x8.5 with 5" Backspacing vs 5.25" BS ? Would that be a show stopper? Would that extra .25" to the outside make a huge difference? Any pictures down the side of a truck with 20x8.5 5.25" Backspacing on a 255/40? ~4.5" drop.

I just want to see how much room it has. .. An 8" wheel will pull my 255/45 in a little so the section width will be about the same as a 5.25" BS 255/40.

Think it would be ok?

Thanks.

Pro Performance · 06-07-2012, 08:59 PM

I don't think a .25" is going to make a hug difference on a static dropped truck. The 4.5" is a pretty good drop though, and might rub some on the inner fender well at the top or the corners when turning.

What wheels are you looking at? Maybe you can google the wheel name and see if you can find pictures of it on a C10, if no one here has that exact backspace.

**CC69Rat** · 06-07-2012, 09:13 PM

It will have a Hellwig front sway bar and worst case I could do modular spindles? .. Humm
the sway bar might hold down the body roll.. ?

Centerline Boulevard ( look like Salt Flats )
Posted via Mobile Device

Pro Performance · 06-07-2012, 09:20 PM

Yes, the modular spindle will move the wheel in 3/4" per side. Is it easier to move the wheel out, than in.

**CC69Rat** · 06-07-2012, 09:30 PM

http://www.classicperform.com/Store/...6GSK-55213.htm

Am I thinking correctly?

Thank You for your help. ..

**screaminchevypickup** · 06-07-2012, 10:08 PM

I had a 5 inch drop on my old truck and at one time with 20x8 and a 4 3/4 bs!!! Rubbed like crazy!!!!
Posted via Mobile Device

**CC69Rat** · 06-07-2012, 10:39 PM

Recall what size tire you had?
Posted via Mobile Device

oldspowered67C10 · 06-08-2012, 12:38 AM

I have the CPP modular spindles w/ the 13" rotors. I have 20x8.5 w 4.75 bs and 255/40-20s, never rubs, couldnt be happier.

06-07-2012, 08:54 PM	#1
CC69Rat Senior Member Join Date: Jan 2011 Location: Chattanooga TN Posts: 6,205	Backspacing question Realizing most people (with 20's) run 20x8.5 up front with 5.25" Backspacing .. 255/40/20 4.5" drop seems to be the norm. I am about to drop my GMC and that's around where I'll be too. I want just a touch more sidewall up front. I have 255/45/20's ready to go. I am about to buy my wheels and I'm down to two. The issue is the ones I really want only come in 20x8 with 4.5" Backspacing. So .. in theory if it were an 8.5" wheel instead it would be the same as 5" Backspacing. Just shove that extra width to the back. .. However: 20x8.5 with 5" Backspacing vs 5.25" BS ? Would that be a show stopper? Would that extra .25" to the outside make a huge difference? Any pictures down the side of a truck with 20x8.5 5.25" Backspacing on a 255/40? ~4.5" drop. I just want to see how much room it has. .. An 8" wheel will pull my 255/45 in a little so the section width will be about the same as a 5.25" BS 255/40. Think it would be ok? Thanks. __________________ Chad 1967 C10 SWB - Project Savannah - 6.0/4L80 Currently underway 1968 C10 SWB - TOTY 2018, 50th Anniversary Tribute Project * Sold * Pride and Joy 1986 Silverado Short Fleet - Scarlet Sold 1985 Silverado Short Fleet Sold 2022 Jeep Gladiator Mojave 2001 Jeep Cherokee XJ 4x4 - Lifted, Built 1992 Jeep Cherokee XJ 4x4 - Lifted 2013 Honda Accord EX-L v6 Coupe 6spd (wife's ride)

06-07-2012, 08:59 PM	#2
Pro Performance Registered User Join Date: Aug 2010 Location: AZ Posts: 3,069	Re: Backspacing question I don't think a .25" is going to make a hug difference on a static dropped truck. The 4.5" is a pretty good drop though, and might rub some on the inner fender well at the top or the corners when turning. What wheels are you looking at? Maybe you can google the wheel name and see if you can find pictures of it on a C10, if no one here has that exact backspace.

06-07-2012, 09:13 PM	#3
CC69Rat Senior Member Join Date: Jan 2011 Location: Chattanooga TN Posts: 6,205	Re: Backspacing question It will have a Hellwig front sway bar and worst case I could do modular spindles? .. Humm the sway bar might hold down the body roll.. ? Centerline Boulevard ( look like Salt Flats ) Posted via Mobile Device __________________ Chad 1967 C10 SWB - Project Savannah - 6.0/4L80 Currently underway 1968 C10 SWB - TOTY 2018, 50th Anniversary Tribute Project * Sold * Pride and Joy 1986 Silverado Short Fleet - Scarlet Sold 1985 Silverado Short Fleet Sold 2022 Jeep Gladiator Mojave 2001 Jeep Cherokee XJ 4x4 - Lifted, Built 1992 Jeep Cherokee XJ 4x4 - Lifted 2013 Honda Accord EX-L v6 Coupe 6spd (wife's ride)

06-07-2012, 09:20 PM	#4
Pro Performance Registered User Join Date: Aug 2010 Location: AZ Posts: 3,069	Re: Backspacing question Yes, the modular spindle will move the wheel in 3/4" per side. Is it easier to move the wheel out, than in.

06-07-2012, 09:30 PM	#5
CC69Rat Senior Member Join Date: Jan 2011 Location: Chattanooga TN Posts: 6,205	Re: Backspacing question http://www.classicperform.com/Store/...6GSK-55213.htm Am I thinking correctly? Thank You for your help. .. __________________ Chad 1967 C10 SWB - Project Savannah - 6.0/4L80 Currently underway 1968 C10 SWB - TOTY 2018, 50th Anniversary Tribute Project * Sold * Pride and Joy 1986 Silverado Short Fleet - Scarlet Sold 1985 Silverado Short Fleet Sold 2022 Jeep Gladiator Mojave 2001 Jeep Cherokee XJ 4x4 - Lifted, Built 1992 Jeep Cherokee XJ 4x4 - Lifted 2013 Honda Accord EX-L v6 Coupe 6spd (wife's ride)

06-07-2012, 10:08 PM	#6
screaminchevypickup Laid Back Join Date: Apr 2010 Location: mcloud ok Posts: 2,658	Re: Backspacing question I had a 5 inch drop on my old truck and at one time with 20x8 and a 4 3/4 bs!!! Rubbed like crazy!!!! Posted via Mobile Device __________________ 72 chevy swb Direct dealers for.. Vintage Air, Porterbuilt, Billet Specialties,Budnik wheels ,eddie motorsports, raceline wheels, intro wheels, Dakota Digital, precision, unisteer, Trimparts, and many many more... Laid Back Recreations.. Full restoration shop and full paint and body.. Kyle http://67-72chevytrucks.com/vboard/s...d.php?t=574629

06-07-2012, 10:39 PM	#7
CC69Rat Senior Member Join Date: Jan 2011 Location: Chattanooga TN Posts: 6,205	Re: Backspacing question Recall what size tire you had? Posted via Mobile Device __________________ Chad 1967 C10 SWB - Project Savannah - 6.0/4L80 Currently underway 1968 C10 SWB - TOTY 2018, 50th Anniversary Tribute Project * Sold * Pride and Joy 1986 Silverado Short Fleet - Scarlet Sold 1985 Silverado Short Fleet Sold 2022 Jeep Gladiator Mojave 2001 Jeep Cherokee XJ 4x4 - Lifted, Built 1992 Jeep Cherokee XJ 4x4 - Lifted 2013 Honda Accord EX-L v6 Coupe 6spd (wife's ride)

06-08-2012, 12:38 AM	#8
oldspowered67C10 Registered User Join Date: Jan 2006 Location: Cherry Valley,Ca Posts: 468	Re: Backspacing question I have the CPP modular spindles w/ the 13" rotors. I have 20x8.5 w 4.75 bs and 255/40-20s, never rubs, couldnt be happier.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.