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Unread 03-01-2013, 10:19 PM   #1
irishluck
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Do I need backspacing or not?

I just received my 3.5 Skyjacker lift kit.
But I cant put it on yet cause I want to get my new tires first.

My question is this. I'm also purchasing new wheels. 16x8 5x5 bolt pattern, black rims. There the same as stock except black.
(Maybe I should just save the $300 for new wheels and just paint them myself)

I need to know though if I'm going to need a new wheel with back spacing or a spacer.

Id like to put 33x10.5 or 33x11.5 tires on my jeep. With the tires and lift, that should give it a 5.5" lift total.

Can someone maybe help me with the back spacing question? It would be very helpful! Thanks!

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Unread 03-01-2013, 11:01 PM   #2
JLC08JK
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The ideal back-space for a JK is about 4 1/2". The factory wheels have just over 6" of back-space and will require 1 1/4" - 1 1/2" wheel spacers to put them in the desired range.
There is more info on tires and wheels in the JK F.A.Q./WILL IT RUB, listed at the top of this forum in the stickies.
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Unread 03-01-2013, 11:03 PM   #3
Filthy-Beast
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Stock is 6.25" backspace, As you go up in tire size you need less back space to push the wheels out, If you don't they with either rub or you'll need to add washers to the wheel locks. Either way you loose turning radius if don't decrease back spacing, 4.5 to 4.75" of back space is what people generally shoot for with aftermarket rims or by adding spacers.
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Unread 03-02-2013, 09:30 AM   #4
thedirtman
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If you are going to put on a 33x10.5" tire you can do it with the factory wheels, not sure why you are doing a 3.5" lift to run 33's? Makes no sense at all. If you go to a 33x12.5" tire you will want to run a 4.5" bs wheel or 1.75" wheel spacers.

There is no reason you cant install the lift before the tires other then it will look funny, it is going to look funny running 3.5" lift with 33's as well.

Your profile lists you have a dana 35 front axle, it is really a dana 30. More detail in the profile would be nice too.
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Unread 03-02-2013, 10:22 AM   #5
JTPhoto
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Quote:
Originally Posted by irishluck
Id like to put 33x10.5 or 33x11.5 tires on my jeep. With the tires and lift, that should give it a 5.5" lift total. !
3.5" lift is too much for 33" or even more then required for 35" tires. The factory tires are already 32" so you won't be getting 5.5" of lift. Going from a 32 to 33" will give you 1/2" lift if you are lucky. Going to a 35 will give you an 1 1/2.

4.5" backspace is standard.
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Unread 03-02-2013, 10:55 AM   #6
irishluck
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Quote:
Originally Posted by JTPhoto View Post
3.5" lift is too much for 33" or even more then required for 35" tires. The factory tires are already 32" so you won't be getting 5.5" of lift. Going from a 32 to 33" will give you 1/2" lift if you are lucky. Going to a 35 will give you an 1 1/2.

4.5" backspace is standard.
My stock tires are 29"

Stock Tire - 235/75R16

Section Width: 9.25 in 235 mm
Rim Diameter: 16 in 406.4 mm
Rim Width Range: 6 - 8 in
Overall Diameter: 29.87 in 758.69 mm
Sidewall Height: 6.93 in 176.02 mm
Radius: 14.93 in 379.22 mm
Circumference: 93.83 in 2383.2 mm
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Unread 03-02-2013, 10:58 AM   #7
irishluck
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Quote:
Originally Posted by thedirtman View Post
If you are going to put on a 33x10.5" tire you can do it with the factory wheels, not sure why you are doing a 3.5" lift to run 33's? Makes no sense at all. If you go to a 33x12.5" tire you will want to run a 4.5" bs wheel or 1.75" wheel spacers.

There is no reason you cant install the lift before the tires other then it will look funny, it is going to look funny running 3.5" lift with 33's as well.

Your profile lists you have a dana 35 front axle, it is really a dana 30. More detail in the profile would be nice too.
So what size tire should I put with a 3.5" lift? maybe a 35" tire? would a 35" would on a factory 16x8?

Oh i can install it without the tires, I just don't want to pay for two vehicle alignments. Rather just do it all at once.

(Yea i made a mistake putting the dana 35 as the front, I forgot to change it.
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Unread 03-02-2013, 11:07 AM   #8
Filthy-Beast
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changing tires won't require an alignment.
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[SIZE="1"][B]97 TJ:[/B] daughter 1 - 2.5L, Auto, 2" BB, 31" GY Duratrac
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[B]06 LJ Rubicon:[/B] mine - Rokmen full up-armor, 8 adjustable CAs, front bumper, sliders, corners, Shrockworks rear bumper, 3" AEV/BDS lift, Currie HD stearing and Antirock, MT/r - k 35x12.5, SuperWinch, MC Overlines, York OBA
[B]13 JKU Rubicon:[/B] Wife's for now, Ace Rock rails & rear bumper tire carrier, Truck Lites, MC Game changer 3.5 lift, RR skids, PSC Brawler front bumper, Warn 9.5cti-s, 35" GY MTRs[/SIZE]
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Unread 03-02-2013, 11:08 AM   #9
irishluck
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Quote:
Originally Posted by Filthy-Beast View Post
changing tires won't require an alignment.
Well I know a lift will.

But your saying adding bigger tires to a vehicle wont require a alignment?
I thought you always did
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Unread 03-02-2013, 11:24 AM   #10
JTPhoto
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Quote:
Originally Posted by irishluck

My stock tires are 29"

Stock Tire - 235/75R16

Section Width: 9.25 in 235 mm
Rim Diameter: 16 in 406.4 mm
Rim Width Range: 6 - 8 in
Overall Diameter: 29.87 in 758.69 mm
Sidewall Height: 6.93 in 176.02 mm
Radius: 14.93 in 379.22 mm
Circumference: 93.83 in 2383.2 mm
So are these the stock sport wheels then? Not many people run those. That now brings up another issue. Generally the small sport wheels also come with 3.21 gears.
So you are correct 33s may give you 2" extra.
33" can be run on stock suspension or up to 2" is nice.
35" can be run on stock suspension with flat fenders but 2.5" - 3.5" lift is preferred.

No alignment required for bigger tires.
Depending on what parts are changed for the lift will determine whether or not an alignment is required. You may only require steering wheel recentering after the lift.
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Unread 03-02-2013, 11:56 AM   #11
irishluck
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Quote:
Originally Posted by JTPhoto View Post
So are these the stock sport wheels then? Not many people run those. That now brings up another issue. Generally the small sport wheels also come with 3.21 gears.
So you are correct 33s may give you 2" extra.
33" can be run on stock suspension or up to 2" is nice.
35" can be run on stock suspension with flat fenders but 2.5" - 3.5" lift is preferred.

No alignment required for bigger tires.
Depending on what parts are changed for the lift will determine whether or not an alignment is required. You may only require steering wheel recentering after the lift.
Yes those are the stock ones.
My wheels are 235/75r16
I just have the 2013 2dr wrangler sport.

I bought the skyjacker 3.5"(SKYJK25BPH) (The price was good for $380 shipped) I included an image in the listing.
So with this knowledge that you guys have now, would it be better to run 33's or 35's?

While im on this topic too. In the picture, there are a few brackets that I am unaware of the fitment location.

Skyjacker didn't include a instruction and there site doesn't either.

The round and the little rectangle brackets under the coils in the image are the stop bump brackets. But the long bracket in the bottom of the image and the one at the bottom left of the image, I have no idea where they go.

So with those brackets, would I need an alignment then?
jk25bph-r.jpg  
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Unread 03-02-2013, 12:19 PM   #12
JLC08JK
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Here are the instructions for a similar kit > http://skyjacker.com/Instructions/JEEP/JK2501BPH.pdf
They are the closest I could find, it looks like the only thing you don't have is the lower control arms so ignore that part.

Here is the kit you show > http://skyjacker.com/product.php?ProdID=29694
The instructions are listed in the "products" link at the top of that page.

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Unread 03-02-2013, 02:30 PM   #13
Filthy-Beast
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Quote:
Originally Posted by irishluck View Post
Well I know a lift will.

But your saying adding bigger tires to a vehicle wont require a alignment?
I thought you always did
Not needed, a change in tire size does not change the relationship, geometry, between any of the suspension parts.
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[B][URL="http://www.jeepforum.com/forum/f22/beast-2-build-13-jkur-1460311/"]13 JKUR Build thread[/URL][/B]

[COLOR="red"][B]For Sale:[/B][/COLOR] [URL="http://www.jeepforum.com/forum/f129/jk-4dr-black-painted-hard-top-1000-a-1541186/"][COLOR="Blue"]2013 4dr JK Painted black Hard Top[/COLOR][/URL] [URL="http://www.jeepforum.com/forum/f127/jkur-18-59-springs-shocks-1557427/"][COLOR="Purple"]JKUR 18/59 springs and shocks[/COLOR][/URL]

[SIZE="1"][B]97 TJ:[/B] daughter 1 - 2.5L, Auto, 2" BB, 31" GY Duratrac
[B]98 TJ:[/B] Daugher 2 - 4.0L, 5spd, D44 rear
[B]06 LJ Rubicon:[/B] mine - Rokmen full up-armor, 8 adjustable CAs, front bumper, sliders, corners, Shrockworks rear bumper, 3" AEV/BDS lift, Currie HD stearing and Antirock, MT/r - k 35x12.5, SuperWinch, MC Overlines, York OBA
[B]13 JKU Rubicon:[/B] Wife's for now, Ace Rock rails & rear bumper tire carrier, Truck Lites, MC Game changer 3.5 lift, RR skids, PSC Brawler front bumper, Warn 9.5cti-s, 35" GY MTRs[/SIZE]
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Unread 03-02-2013, 03:31 PM   #14
irishluck
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Quote:
Originally Posted by Filthy-Beast View Post
Not needed, a change in tire size does not change the relationship, geometry, between any of the suspension parts.
Hm cool. I didn't know that.

If I decide to keep my stock wheel, I'm prolly going to need to get a 2" wheel spacer wont i?

I haven't decided yet if I'm going to just paint mine or buy new ones.

With this lift kit (3.5) don't I need a brake line extension bracket or something?
This kit didn't come with anything for the lines.
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Unread 03-02-2013, 04:28 PM   #15
thedirtman
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Depends on the size of tires you are going to run, you should need extended brake lines or relocate the bracket on the frame down a couple of inches.
That kit is missing a lot of things, thats why it only cost $380.
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