UCA clearance, wheels, tires and chains...

New Tacoma guy, old time Jeep guy here. I'm working on a near stock, Gen 2, TRD access cab, looking at tire and wheel fit (and lift options). Only mod is previous owner 2.25" strut spacer.

After crawling around the truck with a tape measure, with the wheels turned in various positions, the first issue I am noticing is that any larger tire size (either in width and or diameter) is likely going to cause issues with the tire rubbing on the upper control arm.

The stock 265/70 16's on the stock 16x7 +25mm offset wheels barely clear (see pic). No way in heck you could I run chains up the front with this set up, let alone a much bigger tire.

First question, does anyone have a tire size / wheels size / back space measurement guide of some sort to show how much back space is needed for a given wheel width and tire size, to produce a given amount of clearance around the UCA? I'm seeing all kinds of posts on wheels and tires, but none seem to really hone in on any specific UCA Clearance measurements. Ya your tires "fit", but how much room between the tire and the UCA did you end up with?

I was thinking of using a 17x7 with +4mm offset (that's only like 3/16" offset) but from what I'm measuring, I really don't think a 255/75 will clear the UCA, even though I'd be gaining a little over 3/4" of "inside clearance" from the wheel, plus a little by moving from the 265 to the 255 tire.

Ideally I'd like to have clearance to run a heavy duty tire chain (not the phoney cable kind, but real chains), but I think that would require some very aggressive negative offset, with minimal back spacing, even for tires in the 255 or 265 range? Really perplexed how people are fitting 285's on these things. Maybe my truck is some kind of anomaly? Is this strut spacer a contributing factor?

Second question, how much clearance between the tire and the UCA, and the UCA and the Spring, can you expect to gain with an aftermarket UCA? I'm just looking at every possibility to make room here. Planning to ditch the spacer for an OME coil, but wondering if UCA's are also worth the effort?

P.S and off topic - anyone know where I can get a 70 series, left hand drive, Land Cruiser?

 

I'm not sure if I'm answering your questions directly but I can provide some info;

I run 255/75/17 BFG Ko2s on 1st gen tundra/sequoia multi-spoke wheels (17x7 with about 4.75 back spacing) and JBA upper control arms. I have plenty of clearance for chains on my 2nd gen (truck chains have been used, not cables)

As measured from the edge of the tread block, I have about 2 inches of clearance to the UCA, measured from the sidewall is closer to 1 inch of clearance.

 

I only run chains on the rears as not really into ripping out the front brake lines and as you said no room to clear.
Where would you need to chain up all 4 wheels - by then the clearance underneath will load up with snow and you will not move anyway.
I use for ice and clay mud situations and never needed in snow yet.

 

Much better traction and steering on ice if you chain the fronts instead of the rears.

 

If you read your owner's manual you will see that Toyota only recommends rear chains.

 

I know, it's so sad. Toyota is really losing its way, designing for the pavement only market.

 

Makes sense to design vehicles for the use case of the majority. Not a lot of money in niche markets.

 

Chains on the front work REALLY well in the right situations. I live in the mountains of Northern CA and have chained up the fronts on more than one occasion in order to get where I wanted to go. I purposely go out and experiment with chaining up front vs rear vs all 4; you don't know what you and your truck are capable of until you go out and try.

They're especially useful in the kind of snow that packs and turns to ice immediately; even in situations where that snow isn't deep enough to cause clearance issues.

Like anything else, they're a tool. You have to know their limits and use them appropriately. Take the time to fit them appropriately, check for clearance, and keep them tight and you most likely won't have any issues with them like ripping out brake lines. In the handful of times I've seen them tear off sensors or brake lines the operator was at fault for not keeping them tight, failing to install them properly, or using the wrong chains.

Additionally, snow has MANY different types, there really isn't a one size fits all solution. It's pretty normal to encounter many different types of snow on a single day depending on previous tracks, weather conditions, shading etc.

My wheel and tire selection generally has chain clearance as a consideration, and I think that's what the OP is getting at.

 

Chaining up the fronts only is usually asking for the rear end to swing around and get you in real trouble - never never use on a paved road!
Perhaps some play off-road with that setup but generally not advisable. Seen many videos of even the old things we were told "better tires on front" and then the rear lets loose so now better on rears for traction control. We had friends come over a pass with front wheel drive minivan and he chained up the front only and guess what snow bank he ended up in facing the wrong way. No matter 2wd or 4wd if the fronts only are chained the rear can easily swing around.

 

I'm not really looking to debate the best strategy for chaining up. I'm hoping to get feedback on what type of clearance people are getting between the tire and UCA with various wheel, tire and lift combinations. If you have any measurements to share it would be super helpful. Thanks.

 

Thanks for the info. Much appreciated!

 

Any time! Let me know what you decide on. I forgot to mention I'm adjusted to about 2 inches of lift.

 

I'm thinking of trying the Maxxis Bighorn MT in a 275/70 R17, mounted on a 17 x 7 with +4mm offset. I probably won't have enough clearance for chains, but I think it will be an all around good fit. After some measuring, I'm not sure even a 255 would have given me enough room for chains on front. I would have been looking at a negative offset, so I decided to go with a little more tire.