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View Full Version : Rim Offset - How to measure it and get it right



MudRunnerTD
4th October 2011, 08:48 AM
I answered this in a thread and thought i would put it here for all to view, hope it helps.

Firstly this is a Nissan Patrol Forum so note that the standard offset on a Nissan Patrol is +10 or positive 10.

Your offset choice will determine where the wheel sits in your wheel arch and whether it stick out of your guards at all.

On a Nissan Patrol it is very common to increase the offset into the Negative to bring the wheels further out to the edge of your wheel arches to give a wider track and stop bigger tyres from scrubbing on the inner guard.

OK so to get the right measurement you are really going to need a rim off the car or your spare off the door if it is the same. You need to measure the back space of the rim centre to figure out the offset. Offset equals how much the centre of the rim is away from the middle of the rim...

from the diagram below you can see how important it is to know the exact width of your rim. stop into a tyre joint and they will throw a calliper on it for you if you have time or you can figure that out.

Once you have the width of the rim then you halve it to determine the centre of the rim. Offset is how far from the centre of the rim is the centre mounting plate.

OK. You need to lay something across the back side of the rim outer edge of the bead to outer edge of the bead. Then measure the distance from that line to the back of the centre plate of the hub to determine where it is in relation to the rolling rim.

on an 8 inch rim i think they are 200mm wide (you should measure to make sure as every rim is different). zero offset would measure 100mm. Negative 22 offset (considered Toyota offset by most) would measure 78mm to the back plate. Standard Nissan offset of +10 would measure 110mm to the back plate.


69812

^^^^ Now that is a pic of an Alloy Mag wheel. the front of the rim is to the left of the pic and the back is to the right.

or we can get a little technical ;)

69813

69814

69815

Measuring Wheel Offset

To calculate offset you'll need the following measurements:

Wheel backspace
Wheel Width
Wheel Center line (outboard flange to inboard flange measurement / 2)
Subtract:

Wheel center line from Wheel backspace to get offset.
If backspace is less than the wheel centerline the offset is negative
If backspace is greater than the wheel centerline the offset is positive
Tip:

To convert from inches to mm multiply by 25.4
To convert from mm to inches divide by 25.4


An that is that.. Hope that helps you.

Cheers MR

nowoolies
4th October 2011, 08:53 AM
i get my new tyres this week
so while the rims are bare im gunna measure them up
thanks mate the more i read on this forum the more i learn or in most cases get totally confused hahahahahaha...roflmao

AB
4th October 2011, 08:53 AM
Great information MR, we'll sticky this one for sure!

GeeCee
6th April 2012, 03:24 PM
Firstly this is a Nissan Patrol Forum so note that the standard offset on a Nissan Patrol is +10 or positive 10.
Only if we are talking 8" rims.
The offset for 6" rims is +30, so when talking offset, it is important to also note the width that it relates to.
What the difference in offset does for the different rim widths, basically makes the backspace the same (approximately 123mm vs 120mm).

Very confusing when people talk of Toyota offset and Nissan offset.



on an 8 inch rim i think they are 200mm wide (you should measure to make sure as every rim is different). zero offset would measure 100mm. Negative 22 offset (considered Toyota offset by most) would measure 78mm to the back plate. Standard Nissan offset of +10 would measure 110mm to the back plate.
Not quite.
The rim width is the internal distance between the beads. The nissan 16x8 steel GU rim is 203mm between the beads, and approximately 230 from outside flange to outside flange overall, which is the measurement you need.
Using these numbers (230mm),
zero offset is a backspace of 115mm
-22 offset is a backspace of 93mm
+10 offset is a backspace of 125mm

When I measured up some GU 16x8 steel rims, I had a backspace of 123mm which calculated the offset as +8.

When looking at alloy rims, while the rim width will be the same between the beads(for the same rim width obviously), the flange width tends to be thicker than steel rims, so for the same offset, the measured backspace is larger, or to keep the backspace the same, you have a lower offset.

bobrovin
6th April 2012, 08:05 PM
The easiest way to measure the offset without having to even know the rim width is to measure the distance from outside edge to face and from inside edge to face and halve the difference

gavinsell
29th April 2012, 03:19 PM
thanks for the above info MR
i have a question? i measured my offset this afternoon and i got a measuremnet of 101mm from the bead to the front side of the mounting plate and 95 from the bead to the mounting plate on the back side?? would this mean i have almost a 0 offset??
my next question? would this be an ok offset to run a 33 12.5 tyre oh and its a 15x8 rim.

thanks
Gav

MudRunnerTD
29th April 2012, 03:33 PM
thanks for the above info MR
i have a question? i measured my offset this afternoon and i got a measuremnet of 101mm from the bead to the front side of the mounting plate and 95 from the bead to the mounting plate on the back side?? would this mean i have almost a 0 offset??
my next question? would this be an ok offset to run a 33 12.5 tyre oh and its a 15x8 rim.

thanks
Gav

You need to measure through the centre hole to the back mounting face for the front offset to be accurate. The thickness of the centre plate must be measured as part of the front measurement. Measure again. You have the back side so you should be able to get the front with the wheel on the car if you have put it on already.

gavinsell
29th April 2012, 04:18 PM
You need to measure through the centre hole to the back mounting face for the front offset to be accurate. The thickness of the centre plate must be measured as part of the front measurement. Measure again. You have the back side so you should be able to get the front with the wheel on the car if you have put it on already.

make that 107...
Thanks MR

aussiemale
3rd June 2012, 12:00 AM
Thanks MR,

Yendor
22nd June 2012, 06:07 PM
Thanks M/R for the great info.

I was wondering if the offset is also stamped into the back of the alloy rim.

I have performance alloy rims (Storm 17x8s) that have stamped (next to the size) ET 0.

Now, I was told that these rims were neg13 offset when I purchased them, but according to the original supplier/importer they only supplied them in a zero offset.

I haven't measured them as per your first post yet (yes, I am lazy :o ) as usual I am trying the easy way first.

Cheers Rodney

MudRunnerTD
22nd June 2012, 11:31 PM
Hmmm? Sorry not sure Rod, it'd be disappointing if you specifically wanted net 13 and they bolted up zero offset. In reality though now tha they are on the car do they sit how you want them to sit?

I went 16x8 in a neg6 and am very happy there but would go a neg 13 if I ever did it again probably,

Don't be lazy ;) ;) check your spare or get a tyre rotation done and ask them to slip the tyre calipers over the rim while it's off the car. :)

Bigrig
23rd June 2012, 06:05 AM
Hmmm? Sorry not sure Rod, it'd be disappointing if you specifically wanted net 13 and they bolted up zero offset. In reality though now tha they are on the car do they sit how you want them to sit?

I went 16x8 in a neg6 and am very happy there but would go a neg 13 if I ever did it again probably,

Don't be lazy ;) ;) check your spare or get a tyre rotation done and ask them to slip the tyre calipers over the rim while it's off the car. :)

Rod's rims look great ... and yes ... he is lazy coz I've been asking him to wire up some lights for me for ages and he hasn't done it yet!

Oh, by the way ... Rod, I forgot to ask ... could you perhaps spare me some time and wire up some lights for me?? lmfao!!

Yendor
23rd June 2012, 09:12 AM
Hmmm? Sorry not sure Rod, it'd be disappointing if you specifically wanted net 13 and they bolted up zero offset. In reality though now tha they are on the car do they sit how you want them to sit?

I went 16x8 in a neg6 and am very happy there but would go a neg 13 if I ever did it again probably,

Don't be lazy ;) ;) check your spare or get a tyre rotation done and ask them to slip the tyre calipers over the rim while it's off the car. :)

I purchased them second hand and the guy that was selling them wasn't sure so he had them checked and came back with the neg13 offset.

I only have 4 rims so I am trying to find one for the spare. I contacted the original supplier/importer about purchasing a rim and they are now discontinued and she was adamant that they were only available in a zero offset.

I am very happy with how the wheels sits on the vehicle. My concern is if I need to use the spare wheel and it has a different offset what problems would this cause? I'm guessing that wheel will have a different track?

Now, I believe the standard alloys are a zero offset?? so if my alloys are also a zero offset all I need to do is get the correct size tyre and fit it to my standard alloy and this will do for a spare?

But if they are a neg13 offset I will need to purchase a neg13 offset wheel, or do I?

Yendor
23rd June 2012, 09:14 AM
Rod's rims look great ... and yes ... he is lazy coz I've been asking him to wire up some lights for me for ages and he hasn't done it yet!

Oh, by the way ... Rod, I forgot to ask ... could you perhaps spare me some time and wire up some lights for me?? lmfao!!

No worries.

I just had a look at my calendar for the next 3 weeks and it's a bit full. Mansifield tavern, move Scotty, WooHoo boys weekend away.

I'm guessing you need/want it done before then. Looks like I will just have to chuck a sickie :smile:

MudRunnerTD
23rd June 2012, 09:22 AM
Standard Wheels are Positive 10 offset. Maybe he did not take into consideration the thickness of the centre plate? the measurements should be taken from the Seat of the centre plate where it touches the hub.

If the centre of the wheel is 6mm thick then that will put the offset measurement out by 12mm and he might have thought it was a neg 13??

running a different offset on 1 wheel will have Zero effect on the car but will certainly put the track out slightly on 1 wheel. No real drama Rod.

Cheers

p.s.Tell Scotty to google how to wire up lights ;) Google will probably send him back here to one of your useful threads ;)

Yendor
23rd June 2012, 09:36 AM
Thanks mate, I might as well save the coin and use my standard alloy as the spare then.

Scotty will be doing all the work, I will be just watching and drinking his beer.....lol

MQ4EVA
9th December 2014, 04:52 PM
I answered this in a thread and thought i would put it here for all to view, hope it helps.

Firstly this is a Nissan Patrol Forum so note that the standard offset on a Nissan Patrol is +10 or positive 10.

Your offset choice will determine where the wheel sits in your wheel arch and whether it stick out of your guards at all.

On a Nissan Patrol it is very common to increase the offset into the Negative to bring the wheels further out to the edge of your wheel arches to give a wider track and stop bigger tyres from scrubbing on the inner guard.

OK so to get the right measurement you are really going to need a rim off the car or your spare off the door if it is the same. You need to measure the back space of the rim centre to figure out the offset. Offset equals how much the centre of the rim is away from the middle of the rim...

from the diagram below you can see how important it is to know the exact width of your rim. stop into a tyre joint and they will throw a calliper on it for you if you have time or you can figure that out.

Once you have the width of the rim then you halve it to determine the centre of the rim. Offset is how far from the centre of the rim is the centre mounting plate.

OK. You need to lay something across the back side of the rim outer edge of the bead to outer edge of the bead. Then measure the distance from that line to the back of the centre plate of the hub to determine where it is in relation to the rolling rim.

on an 8 inch rim i think they are 200mm wide (you should measure to make sure as every rim is different). zero offset would measure 100mm. Negative 22 offset (considered Toyota offset by most) would measure 78mm to the back plate. Standard Nissan offset of +10 would measure 110mm to the back plate.

http://www.nissanpatrol.com.au/forums/

^^^^ Now that is a pic of an Alloy Mag wheel. the front of the rim is to the left of the pic and the back is to the right.

or we can get a little technical ;)

http://www.nissanpatrol.com.au/forums/


Measuring Wheel Offset

To calculate offset you'll need the following measurements:

Wheel backspace
Wheel Width
Wheel Center line (outboard flange to inboard flange measurement / 2)
Subtract:

Wheel center line from Wheel backspace to get offset.
If backspace is less than the wheel centerline the offset is negative
If backspace is greater than the wheel centerline the offset is positive
Tip:

To convert from inches to mm multiply by 25.4
To convert from mm to inches divide by 25.4


An that is that.. Hope that helps you.

Cheers MR

So all models of Patrol have a standard offset of +10 or positive 10? So I could fit some sunraysias 31x8x15 that came off a GQ and they will fit fine to my MQ? Is the hub size the same?
Thanks

Drewboyaus
9th December 2014, 05:33 PM
So all models of Patrol have a standard offset of +10 or positive 10? So I could fit some sunraysias 31x8x15 that came off a GQ and they will fit fine to my MQ? Is the hub size the same? Thanks

No. Not necessarily so. My GQ was factory fitted with -13 offset 15x7 inch wheels as it was fitted with the "wide wheel pack" flares.....as many later models were.
There would be another offset for a GQ for the model that had cheesecutters and no flares. I don't know what that is though.

Sent from my iPhone using Forum Runner

the evil twin
9th December 2014, 05:47 PM
So all models of Patrol have a standard offset of +10 or positive 10? So I could fit some sunraysias 31x8x15 that came off a GQ and they will fit fine to my MQ? Is the hub size the same?
Thanks

I haven't owned or seen any Patrol Rims with +10. Only factory ones I have seen are either 0 or -13 depending on wheel pack or GQ/GU.
Not sayin +10 isn't out there just sayin' I haven't ever had any.
I definitely wouldn't call +10 as a "standard offset" depending on how you interpret the term.
Is +10 the offset for skinnies maybe?

I use -22 offset rims for any tyre 305, 315 or 12 1/2 width.
Any wider and it starts to load up the hubs and affects the scrub radius more than I am comfy with, again, just my opinion.
-22 stays legal as well in regards track width regs for ADR

MudRunnerTD
9th December 2014, 06:01 PM
I haven't owned or seen any Patrol Rims with +10. Only factory ones I have seen are either 0 or -13 depending on wheel pack or GQ/GU.
Not sayin +10 isn't out there just sayin' I haven't ever had any.
I definitely wouldn't call +10 as a "standard offset" depending on how you interpret the term.
Is +10 the offset for skinnies maybe?

I use -22 offset rims for any tyre 305, 315 or 12 1/2 width.
Any wider and it starts to load up the hubs and affects the scrub radius more than I am comfy with, again, just my opinion.
-22 stays legal as well in regards track width regs for ADR

The GUIV Alloys are Positive 10

The other GU Alloys are all Pos10 too

I also think the GQ Alloys in a 16x8 are a Pos10 also.

MudRunnerTD
9th December 2014, 06:13 PM
I have just grabbed a screen shot of each of the Manuals we host here for reference.

So the 15x7 rim on the early GQ is a Pos5

52545

The 16x8 rim on the GU is a Pos10

52546

and the 17x8 on the later GUIV and onwards is a Pos10

52547

The offset for the Splitties are also listed

the evil twin
9th December 2014, 06:59 PM
The GUIV Alloys are Positive 10

The other GU Alloys are all Pos10 too

I also think the GQ Alloys in a 16x8 are a Pos10 also.

Thanks for sorting that out MR and there ya go, told ya I'd never owned a rim with that offset :o

Interesting thing is it makes every one of us running -22 or more illegal :210:

Ah well, shit happens.:049:

Agronaught
9th December 2014, 07:37 PM
That's interesting as to get steelies to fit I had to go to the 16" -23 kings, nothing else would git over the front calipers except the original alloy wheels.

Not good if its illegal.

MQ4EVA
10th December 2014, 10:42 AM
Thank you very much guys for that informative information about the offsets. I think I think might just drive the MQ all the way to brisbane and fit 1 on the back and front to make sure they are all good before I purchase them. Have a nice week "PATROLLERS" LOL

i_am_swanny
9th November 2016, 08:47 PM
so helpful! love it

MarionCohrs
10th November 2016, 01:23 AM
thanks for this great information. Good info anyway.

Robo
17th November 2016, 01:13 PM
Referring back to story about wrong offset rims supplied new from retailer.
That maybe a common practice, She'll be right, he wont know the difference or notice!!.
Lucky I fitted the spare back on and did notice the stamped offset, fronted salesman that it was not as ordered, he came good.

Some may say, so what! wanting oem specs offset to help ensure less chance of the dreaded wobbles, bump steer issues etc.
Yep offset may not directly cause a wobble but when ya add up any changes to geometry it may help combine to , m2cw.
In the end settled for GQ ti alloys for the std oem offset and quality brand name tyres, +90 000 k's later still steers like new , albit mainly Rd k's.

Spiv
18th November 2017, 02:30 AM
This site: https://www.wheel-size.com/, lets you search for tyres and rims of every vehicle.
You can also find which vehicles fit a certain rim or tyre.
There are calculators to compare OEM tyre with whatever you fancy as well as OEM rims with aftermarket.

See this example for Patrol 98: