Tire size on a 2F powered FJ60 with an OME lift (1 Viewer)

[SurfCruiser32]

First post here, though I’ve been a lurker for years. I have an 87 FJ60 that’s mostly stock except for an OME lift kit with shocks, leaf springs, and steering stabilizer.
Finally replacing the tires that were on it when I bought it - original KO’s 31.5x10.5x15 on some not stock steel wheels and 1.5” spacers.
So I’ve already been through the challenge of finding wheeels that fit without spacers. Settled on the TRD Pro matte black wheels 17x7.
So now it’s tire size time. I’m thinking of staying similar to what I have now with a 265/70/17 BFG KO2 (listed as 31.6) mostly thinking about driving up the passes here on the highway like Snoqualmie pass from Seattle. But also wondering about something like 34x10.5x17 KO2’s (33.5” listed) -just worried about hills. Another option I considered is a 255/75/17 (32” listed)
The 265 and 255 options are listed as about 46lbs while the 34 option is 58lbs. Plus the TRD Pro wheels are around 27lbs.
Any advice or thoughts very welcome.
And yes I’ve searched and looked around but am not finding much about the size with stock 2F and stock 4spd transmission/gearing and highway hills. Thanks!

 

[Seth S]

Anything over a 33" or equivalent on the stock 60 gearing is going to be a challenge for highways and hills. My experience on stock gearing with the 4 speed and 31's is that it drives nice on flat ground and trails I have plenty of torque. For hills or interstates I don't have much reserve power and a long steep hill on a 50 mph road I can probably hold 40-45 if I drop to 3rd.

 

[Gretsch]

And yes I’ve searched and looked around but am not finding much about the size with stock 2F and stock 4spd transmission/gearing and highway hills.

Real world experience. Mine with 33's (32.3 roughly, 10.5), OME, and stock everything else (desmogged however and no HAC or advance adjustments) sucks on the hills. If you are asking this question, then you will most likely hate it with 33's against a hill.

Now in my trucks defense I was pulling the small trailer you see above at the time and was about 5000 feet higher elevation than the pass you mentioned. But think 35-45 Mph on long grades with the 33's. Raton pass was silly. I could have prolly done better advancing the dizzy some or with some other adjustments but didn't. At one point I could only muster 20Mph in second on Colorado 550. I don't care really as I like the 33's. I get there when I get there. If I was interested in speed on grades, I wouldn't be driving this carb'ed dinosaur.

As @Seth S mentions 31's on a stock setup is about where you really want to be with the stock stuff if you are concerned about power on grades. Those are good balance between looks and performance. Anyway that was my experience with OME and 33's. GL and HTH.

 

[OSS]

I had 31" tires on my cruiser for 30 years and drove everywhere anyone could drive in baja with them. Yes there were definitely times I remember thinking I sure wish I had 33s but the 31s when aired down always took me wherever I dared take the vehicle.
There were LOTS of times (like almost always) that I thought the 31" tires and stock gears were a bit too tall when driving on pavement. The cruiser is a lot more fun to drive on pavement with tires SMALLER than 31s.
So 31s are a trade off between street and dirt. They don't excell at either on a stock cruiser but fit nicely as a 50/50 compromise.

 

[SurfCruiser32]

Thanks for the thoughts and real world examples, I appreciate it! I’m gonna stick with closer to 31’s given the advice here.

 

[lonelydriver]

33's with 4.11s from a 62 or 40 series

 

[g-man]

How technical is it to replace ring and pinion gears in the third members? And if you're going to pull them out shouldn't you rebuild the whole thing? Can you do this without a lot of knowledge and specical tools ..ie dial indicator?

 

[Seth S]

How technical is it to replace ring and pinion gears in the third members? And if you're going to pull them out shouldn't you rebuild the whole thing? Can you do this without a lot of knowledge and specical tools ..ie dial indicator?

it’s mostly physical labor. But a dial indicator is a good thing to have as well as feeler gages and a torque wrench. Dial indicators are pretty easy to get...magnetic base can be handy.

its all nuts and bolts until reassembly. But usually it’s just setting gear lash etc at the end that’s the precision part. I’ve not done the third member in a Toyota axle but have done an LSD in a FWD gearbox. There’s some shim adjustments and pinion adjustments to get the lash and preload and all those fun things. FSM and patience.

 

[Super77]

I’m shopping for new tires right now for my near-stock 62. Same thoughts on my mind: 31 vs 33. Right now I have 30” BFG KO2. Reusing my factory 15” rims.

I landed on 31s, but was surprised by the weight difference between tires. A 31x10.5x15 Firestone Destination XT weighs the same as a 30x9.5x15 KO2. In fact, according to Tire Racks’s specs, there is a 8lb weight range in the 31 size among the name-brand best selling AT tires.

So I wonder how big a difference minimizing the rolling mass makes with our F-powered trucks?

 

[60Works]

Lots of good real world advice posted.

31" is a very good compromise size for both 60's and 62's with stock gearing. 31's look good with stock springs. 33's are nice with OME medium springs.

For a tired 2F; 33's are too big. Swap in 4.11 gears and 33's are the same ratio as 31's with 3.70. General consensus is that this ratio is the sweet spot for a factory power plant.

 

[MoaByte]

Good advice here^^.

I bet you'd like 255/75/17's not too tall, not too fat. The Cooper Discovery ST maxx lists it at 50lbs but it's a great tire and quiet.

 

[ntdb]

For what it's worth my BFG KO2s are listed as 33"x10.5"x15" but they measure 31" tall on my 15"x8.5" rims. Switching to 4.11 gearing might be ideal but with these tires I can do 65mph at 2500rpm on the freeway so I'm happy.

 

[MoaByte]

This^^^. Rubber overdrive is worth it. You will be in 3rd gear climbing grades anyway.

 

[Super77]

I can do 65mph

You had me until that part

 

[GeologistFelix]

You had me until that part

To be completely fair, same exact setup (33x10, 3.70 gears, OME lift springs) with an exhaust leak and a partially seized dissy (so, no vacuum advance?) pushed my truck along at 80 mph (confirmed by GPS!) at 7500 feet between SLC and Moab. Took a while to get up that fast, and got about 11 mpg instead of 14.5, but it'll *do* it.

 

[ntdb]

To be completely fair, same exact setup (33x10, 3.70 gears, OME lift springs) with an exhaust leak and a partially seized dissy (so, no vacuum advance?) pushed my truck along at 80 mph (confirmed by GPS!) at 7500 feet between SLC and Moab. Took a while to get up that fast, and got about 11 mpg instead of 14.5, but it'll *do* it.

You're making my 75mph top speed and 12mpg average feel inadequate!

 

[Gretsch]

To be completely fair, same exact setup (33x10, 3.70 gears, OME lift springs) with an exhaust leak and a partially seized dissy (so, no vacuum advance?) pushed my truck along at 80 mph (confirmed by GPS!) at 7500 feet between SLC and Moab. Took a while to get up that fast, and got about 11 mpg instead of 14.5, but it'll *do* it.

You are my hero.

 

[GeologistFelix]

You're making my 75mph top speed and 12mpg average feel inadequate!

Speedo corrected? 3.70 gears + 33s = 80 mph at 3000-3100 RPM. My speedo reads ~71 when the truck is hurtling at that speed.

All of that said? I tend to just go a comfortable speed and keep up with traffic when possible (or pass people when they're going under the speed limit and I've got the oomph to get around them). I'm way, way too poor on a grad student salary for speeding tickets...

 

[ntdb]

Speedo corrected? 3.70 gears + 33s = 80 mph at 3000-3100 RPM. My speedo reads ~71 when the truck is hurtling at that speed.

All of that said? I tend to just go a comfortable speed and keep up with traffic when possible (or pass people when they're going under the speed limit and I've got the oomph to get around them). I'm way, way too poor on a grad student salary for speeding tickets...

My 33s measure 31" tall on my rims so I think that puts me around 75mph at 3000rpm mathematically. My speedo runs slow but I tend to open a speedometer app on my phone when I'm curious about actual speed.

Agreed about the comfortable speed. Part of the reason I got a 60 was to embrace the journey and the 2f does that for me. I love driving it and I am usually amused when semi trucks pass me over mountain passes. I can catch up going down the other side!

 

[MoaByte]

Cruising at 3000 rpm (@75mph) seems fine for the 2F. That where mine sat with BFG 33x10.5. It put the odometer off 14% so multiply gas mileage by 1.14. (3.70 gears).