Wheel offset

Im looking at getting some more rims for one of my 110s. I see the standard offset on steels is -30mm. I have my eye on some of the 7 x 16" challenger wheels sold by 4x4tyres and they have -20mm. I assume my standard rims will be 5.5" or 6" wide.

Can someone explain this offset to me, I mean, where is the measurement made from etc?

Many thanks, Pete.

Offset is measured from the centre of the wheel


Basically your new wheels will mount 20mm further in from the centre of the wheel. Working on the assumption your wheels are 6j (I can't remember exactly, mine aint standard. You will have 23mm less clearance on the inside of the wheel and the outside rim will sit 3mm further out.

Useful little diagram that Jack, cheers.

So, Ive just been out and had a look. My standard rims are 5.50x16x33. So by that I assume they are -33mm offset on a 5.5" rim?

I think Im interpreting your diagram in a different way to you though, as I see it the 13mm difference would push the rim outward wouldnt it?

Given that the new rim would be 1.5" wider too, 3/4" should be added to the 13mm the rim would be pushed outward, making them stick out approx 32mm more, yet be 6mm further in toward the hub, as the extra width is more than the offset difference.

Let me know if you think Im talking bull, I'm used to getting the wrong end of the stick

With a 5.5j to 7 with the offsets you've said you're going to have 32mm clearance less on the inside of the wheel with the new ones and the outer will be 6mm further out. So yeah you've got the right idea mate, unless I've got my maths wrong.
Although it sounds like the ones you have now are positive offset in which case the inside rim will be further out to the outside of the car by 34mm and the outer rim will be 72mm further out.

I'll go and look at the standard wheel I've got in the shed and get back to you.

Yeah standard are positive offset. So inside rim will have 34mm more clearance and outer will be 72mm further out.

Most 7j Land rover alloys are + 33mm offset

Right, ok it sounds like Im back to front! So negative puts the wheel further out, positive sits it in the arch. I was working the other way around.

Unfortunately, it appears the wheels Ive been looking at will not fit in my arches. There is only approx 50mm outside the tyre to the arch.

This will explain why I have to get it right;

You may need to click to enlarge to view correctly;





Many thanks for all the input, I guess I was a little slow on the uptake, but its saved me a useless and expensive purchase.

Cheers, Pete.


.

Yeah 0 offset means the face of the wheel that bolts to the hub is dead central in the wheels, negative means the bolting face of the wheel goes further 'in' pushing the rim 'out'.
'Deep dish' wheels generally have an offset of 0 or less, Some modulars can have a - 32mm or even - 50mm offset, but extended arches would be needed if you wanted it to be legal hope this helps

Am I right in thinking that a positive offset will put more pressure on the wheel bearings thus shortening their life expectancy?

Mark L said:

Am I right in thinking that a positive offset will put more pressure on the wheel bearings thus shortening their life expectancy?

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Yes....the best way to preserve wheel bearings is to remove the wheels altogether, put up on blocks and gently spin the hubs by hand.....ON NO ACCOUNT USE THE VEHICLE.......vehicle use will substanually reduce bearing life and may invalidate guarentee

blue beasty said:

yes....the best way to preserve wheel bearings is to remove the wheels altogether, put up on blocks and gently spin the hubs by hand.....on no account use the vehicle.......vehicle use will substanually reduce bearing life and may invalidate guarentee

Click to expand...

Mark L said:

Am I right in thinking that a positive offset will put more pressure on the wheel bearings thus shortening their life expectancy?

Click to expand...

The more positive the wheel offset, the problem you're going to face is the tyre fouling the radius arms on full lock. As far as I know the only way you're going to get a worse expectancy from bearings is if you use spacers, because you are mounting the wheels in a physically different place. Fitting spacers will have the same effect (wheel position) as having a negative offset of the same size as the spacer. I think you probably meant if a negative offset would affect wheel bearings? If so I honestly don't know, going around corners and moving shortens the expectancy of wheel bearings tbh

I meant significant shortening, not general wear & tear.

The reason I asked is because I was considering a set of wheels with a 30mm wider offset & some wider tyres, say 265s or 285s, but not if it means I'll be changing wheel bearings every 12 months or so.
Current wheels are standard 7J with 235s.

The 'best' offset for bearing life is et0. Moving the mounting point either side of that is going to have an effect on the bearings, just on a different side of the bearing depending if you are running positive or negative offset. Tbh though its negligible unless you're running something like 10j with a ridiculously low offset. If you're bearings are good then you wont be changing them as often as you think and definately not every 12 months or so

Guys I too have a question to wheels. My present old steel wheels are 16" x 5.5" on my 1991 Def 110.

Now I want to upgrade to 16" x 8" steel wheels and they have a "0" offset. Is this ok for my Landy. I plan on using 285/75/16s ot 265/70/16 tyres on these wheels.

Is it ok to buy the 16 x 8 ZERO offset wheels?

Prith said:

Guys I too have a question to wheels. My present old steel wheels are 16" x 5.5" on my 1991 Def 110.

Now I want to upgrade to 16" x 8" steel wheels and they have a "0" offset. Is this ok for my Landy. I plan on using 285/75/16s ot 265/70/16 tyres on these wheels.

Is it ok to buy the 16 x 8 ZERO offset wheels?

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If you look at my profile pic - my wheels are 16x7 with 0 offset. Tyres are 285/76 - 16 and stick outside the arches a fair bit. Would not be quite so bad with a normal shape tyre though, as the Insa's lugs stick out a long way!!

Sorry Chaps yet a couple of years late, i have a 110pickup, and was planning on putting these steels on, please see pics, 16 x 8 with ET32 and tyre size 285/75/16. I appreciate extended arches will be needed but can I get away without spacers if I adjust the stop locks

If not I can go for 265/75/16 tyres

I would like to wide track my defender 90 but don’t want to use spacers if I don’t need to what offset do I need ? If I haven’t provided enough info just ask me. I’m still learning.

Archer07 said:

I would like to wide track my defender 90 but don’t want to use spacers if I don’t need to what offset do I need ? If I haven’t provided enough info just ask me. I’m still learning.

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Out of interest, why?