Stock TRD Pro with 255/85r16 Cooper Discoverer ST

There have been multiple people asking about largest tires to fit whichever model, etc, etc, etc. Here is a new one, which I have not seen anywhere.

I have a straight stock 2017 TRD Pro. On Monday I got a set of five Cooper Discoverer ST 255/85r16. Based on calculations, it is 33.1" tall. Actual measurement mounted, but not weight bearing, it was 33". Bearing the vehicle weight it's about 32.5". I don't know the tire pressure right now.

There has been no interference with the UCA, I will attach some rough photos. Also, the straight ahead clearances of the front leading is 1.75" and trailing front a hair over 2"". The closest the leading edge of the front tire comes on a flat turn is a little under 1". The closest the trailing edge of the front tire comes on a flat turn is a hair over 1". The rear tire has a leading 3" and trailing 2" clearance. These could all be increased by remolding the liners or trimming.

After a week, I have had no rub. I have not been offroad, but I live in a unique location and my driveway and access roads require some fairly extreme off camber turns that lead into steep ascents. This means that I do flex quite a bit, but I do not max it out. Still, with these turns and angles, no rubbing so far.

A common problem with 255/85 and 285/75 on 16" wheels, is mounting the spare. I took a lesson from the second generation guys. The spare 255/85r16 will hit the exhaust pipe, which is not good.

I took some measurements and felt that if I could get the standoffs flat, I could get the stock spare carrier to work without relocation. So, I got a big hammer out and flattened the standoffs. I was actually really surprised and even a bit disappointed at how soft the metal was. If the frame is made of the same materials, there are going to be a lot of bent frames out there.

Once the standoffs were flat, I greased the hoist chain and installed a small lock (really well greased) on the spare fitting at the end of the chain. As I raised the hoist, I had to pull back and a little to the left to get the tire away from the exhaust as possible. I'll drive around next week and recheck to see if it shifts. If it gets closer to the exhaust, I'll tether it to the left.

All in all, I love the combination of 255s with the Pro. I love the look, I love the traction in snow, and I love the way that this all came together without any significant modifications.

Any questions, just ask. Here come the pictures.

 

Very nice

I also have extreme camber coming up to my house

I am going down to 235/245 pizza cutters on mine

Also I am looking to drop significant weight from the stock tires

 

Uh I think you just sold me on a tire size

 

30 foot rise on a 45 foot run. Try plowing that with a foot of snow! From December to March, if you don't have 4 wheel drive, you aren't going to visit me. I've literally thought of putting in a chair lift.

 

Same here coming up to the mountain
But no snow

I use my 4wd at Starbucks

 

Dork.

 

Very nice. I wonder if a stock Off Road will be able to fit the tire size as well as the TRD Pro. Isn't the TRD Pro slightly lifted as compared to an Off Road or Sport model? Anyone try this tire size on a stock non-Pro 3rd gen?

 

The pro is supposed to be one inch higher up front than the non-pros, but the back is the same. Also the pro wheels are supposed to be set out a half inch on each side, for a one inch wider track. Will this be enough to make a difference? I think so. However, could you mitigate those differences with some trimming or liner remolding? I think you could. It just depends on how much you are willing to do to it.

When I made the decision on these tires, I had already decided to trim plastic, heat mold the liners, and comic if necessary. However, I haven't needed to do any of that at this point.

 

Thanks for the write up!! Great info

Keep us updated if anything unforeseen comes up please

 

How does the truck drive with them and stock diff gearing? With the 3rd gen's lack of low end torque and auto tranny's eco geared, I'm interested to hear if there is any major impact to how the truck drives now with the stock engine/tranny/diff combo.

 

Thats a good looking tire size. I think an OR rim with a 1.5 spacer would be perfect looking with that tire setup. Someone try that and get back with me so i can see if it works. thanks

 

Looks awesome, excellent pics/measurements too! Gota see pics of that crazy driveway though.

I'm waiting for someone w/a stock SR to try this size before I do, I have a feeling being at least 1" lower ride height and 0.5-1" closer offset wheels I'd have some rubbing on full lock...

 

It's a manual. First is perfect. Honestly the tranny feels like it was meant for 33s to me. I haven't put it into 4lo though. Can't comment on that.

 

Thanks, I'll wait for next big snow storm and take pics for the full effect. I put 200# of salt on it today. I have to buy it by the pallet.

 

Good call on this tire size. Tall pizza cutters are seriously underrated by the bros IMO.

 

Big thank you to the OP for this excellent write up and all the pictures. I think this looks to be an excellent tire size for the 3rd gens. I have a 2016 TRD OR and would be very interested to know if this specific tire size would work out with the oem TRD OR 16" wheels, or would spacers be required.

Thank you

 

I am wondering the same, but according to 2nd gen tacos, they do fit well without any spacers. Only requirement is a 2" or higher lift, which will help prevent rubbing

 

Well I'm about to order for a 17 offroad and put them one stock wheels with no spacers. So I'll let you guys know.

 

I have and Off road and installed the same size tire with Maxis Bighorn. I had them initially installed with no lift or wheel spacers and the only rubbing I had was during sharp turns when flexing. I did put on some spider tax wheel spacers which really helped the overall stance but made it rub a littler worse. Due to this, I put mild 1 inch spacers front and rear until I can get the Bilstien 6112. I will post a pic today, but I think this tire combination is the perfect set up for snow, ice and mild offloading....