Backspacing question?
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From: orange county ca.
Backspacing question?
I'm looking at some rims that are 20x8 in the front with 4.54 backspacing and the rears are 20x9.5 with 5.29 backspacing.
My truck is going to have DJM drop beams in the front with a flip kit in the rear. Tires I was thinking about running are 255/45/20 in the front and 295/40/20 in the rear.
I have read to keep the backspacing around half of the wheel width so I was wondering if I'm going to run into issues with rubbing?
Any help before I decide to buy would be great!
My truck is going to have DJM drop beams in the front with a flip kit in the rear. Tires I was thinking about running are 255/45/20 in the front and 295/40/20 in the rear.
I have read to keep the backspacing around half of the wheel width so I was wondering if I'm going to run into issues with rubbing?
Any help before I decide to buy would be great!
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Senior User
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From: orange county ca.
Thanks Christmas for the videos. I will see if I can measure this weekend. Before I get to that I’d like to hear if anybody has experience with running a rim with more backspacing them half the width. Btw these rims are a +1 mm offset.
Mountain Pass
Joined: Aug 2019
Posts: 187
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Backspacing at half the width = 0 offset.
The rear drums have about 5.5" of protrusion from the stock inner fenders. However, the 295/40 rear will wider than the rim and so you will be REALLY close. If one side of the truck rolls over something higher than the other side, it will scrub the inner tubs.
The fronts will be "okay" but will reduce your turning radius at 4.5" backspace with a 9" tire. It will scrub at wheel lock just a tiny bit.
The rear drums have about 5.5" of protrusion from the stock inner fenders. However, the 295/40 rear will wider than the rim and so you will be REALLY close. If one side of the truck rolls over something higher than the other side, it will scrub the inner tubs.
The fronts will be "okay" but will reduce your turning radius at 4.5" backspace with a 9" tire. It will scrub at wheel lock just a tiny bit.
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From: orange county ca.
Thank you for the response pcmdub. So if I understand your post if I was to run a 245/45 on the front and a 285/40 in the rear(or something similar in size) then I should be ok as far as rubbing. I wasn’t set on those sizes for tires. I’m just going off of what others have done. I’m even open to running 20x8’s front and back if it will work better.
Tuned
Joined: Nov 2014
Posts: 344
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I'm looking at some rims that are 20x8 in the front with 4.54 backspacing and the rears are 20x9.5 with 5.29 backspacing.
My truck is going to have DJM drop beams in the front with a flip kit in the rear. Tires I was thinking about running are 255/45/20 in the front and 295/40/20 in the rear.
I have read to keep the backspacing around half of the wheel width so I was wondering if I'm going to run into issues with rubbing?
Any help before I decide to buy would be great!
My truck is going to have DJM drop beams in the front with a flip kit in the rear. Tires I was thinking about running are 255/45/20 in the front and 295/40/20 in the rear.
I have read to keep the backspacing around half of the wheel width so I was wondering if I'm going to run into issues with rubbing?
Any help before I decide to buy would be great!
My front wheels have 0" offset and 4.50" backspace.
My rear wheels have 6mm offset and 5.75" backspace.
Front wheels went on fine. No rubbing, no issues.
When I installed the rear wheels the tire rubbed the bed.
I had to install 1" spacers to prevent the rubbing.
The rear wheels are now centered in the rear wheel wells. I have almost exactly 1" of clearance on each side of the tire.
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From: orange county ca.
Thanks Fleetwood. You are the one I got my tire sizes from. This answers my question and if I don't want to run the spacer then I can just go with 20x8's all the way around and do a slightly smaller tire.
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Mountain Pass
Joined: Aug 2019
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So if you got 20x8" rims, then the normal backspace is 4.5" and a 245 tire will fit. Here is the chart for you
https://cdn.discounttire.com/sys-mas...sion-chart.jpg
However, you will have 2 inches between the OUTSIDE edge of the tire and the fender. This may not be the look you want. So then people get into spacers....YIKES. Many spacers are now built to high standards, but there are several that have questionable engineering. So you are ALWAYS better off getting wheels that just fit right from the start...
If you want 20x10, then you just need wheels with 4.75 backspace or less and a tire that is not much wider than the rim.
Hope that helps...
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From: orange county ca.
Pcmdub I total understand what you are saying and if I could find rims that I liked at an affordable price in the right back spacing then I would buy them.
5 x 5.5 rims that aren't custom made that meet that back spacing are hard to come by. Like I asked above if I was to run a tire like a 285/40 on the rear with the 9.5 rim with the backspacing of 5.29 then I should have more room and it shouldn't rub, right?
5 x 5.5 rims that aren't custom made that meet that back spacing are hard to come by. Like I asked above if I was to run a tire like a 285/40 on the rear with the 9.5 rim with the backspacing of 5.29 then I should have more room and it shouldn't rub, right?
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From: orange county ca.
Another idea I had was running 20x8.5 rims on front and back and running 255/45 tires all the way around. Then I could buy a high quality 1 inch spacer for the rear. This would give me the “look” of filling the wheel well and it wouldn’t rub at all. Bonus would be that I can rotate the tires!
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