Best all-around tire size

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I had an 81 FJ40 and my friend has an 82. Between both of us we have gone through many sizes if tires. On my 81 I ran a 30X9.5 sport king, good tire for stock setup. Next I moved to a 33X9.50 BFG Mud Terrain, really liked the tire, thought they might have been too narrow for alot of situations. Next I went to a 33X12.50 BFG Mud Terrain, really liked the look, but found them to be to wide for daily driving. My other friend has run 32X11.50 BFG All Terrain, good daily driving size, I think they look a little to small in the wheel well. I finally found the perfect tire when my other friend with a 78 40 put on the 33X10.50. Great height, good all-around width, looks great in the wheel wells. By the way, the 82 has a 2.5" skyjacker lift, the 78 had a shackle reversal with 2.5" BDS, and my 81 had a 2.5 OME with 2" shackle. The 33X12.50 rubbed on the inner rear wheel well on my 81.

Gearing -- I ran the 33X9.5 with 3.73 gears and really noticed a power loss compared to stock size tire. I regeared to 4.11 when I put on my 33X12.5 which made a world of difference, I could not believe how much better it ran on the highway and over the canyon. I have been told that for every inch of larger tire you will loose on tenth of your ratio. For example if you go from a 29" tire(roughly stock) to a 33" tire and you are running 3.73 you gear ratio will actually be about 3.33. When you regear to 4.11 it returns your ratio back to roughly 3.73(stock).

Sorry for all the rambling, I tried to make it quick.

Scott
 
IMO the 31's are not only are the perfect fit asthetically for your rig, they are a better match for your drivetrain than the 33's would be be cause you'll have more power and less mechanical stresses with the smaller tires.
 
What kind of cost/hassle am I looking at to regear. I'll do a search and check the technical how to section but if anyone knows of the top of their head.... ;)
 
I did all of the labor on mine, but I was able to get a ring and pinion from a 74 crusier that was in great shape. If you can get the ring and pinion used then I would buy all of the bearings new. When I did it I also put in ARB's front and rear. The cost of the bearing kit (bearings, shims, etc...) was about $150 per axle. I beleve that new ring and pinions run in the neighborhood of $300 per axle, but you could check Randy's Ring and Pinion. With the 4 speed and 33 I would run 4.11 gears.

Thanks
Scott
 
As for the hassle, it is a fairly techincal job. You need a couple of special service tools and a good manual. Setting the backlash is probably the most techincal part. I was also told that if you are using used ring and pinions you will want to shim the pinion the same as when it came out. On older ring and pinions you can't alway get the perfect wear pattern, so just using what shims were in there works the best. I hope this helps.

Thanks
Scott
 
[quote author=ClimbingCruiser link=board=1;threadid=14676;start=msg139588#msg139588 date=1082036500]
With the 4 speed and 33 I would run 4.11 gears.

Thanks
Scott

[/quote]

Scott,

How bad/good was it running 33's with the 3.70 ring and pinion? In your previous post you said you really noticed a power loss running 33's with the 3:70. You might think I'm nuts, but I'm seriously considering changing my stock 4:11's in my 77 now to 3:70's. I'm not into the whole off roading seen, trying build more of a daily driver. Just seems like right now going down the highway I need another gear on the top end.

I'm going to get a timing light, hook it up and run down the highway at 60 mph and see what my rpm is, just seems like the motor is tached up pretty high? After my resto and all the upgrades I installed to make it road worthy sure made a difference. It actually drives pretty nice down the highway at 60 now, I wouldn't mind even going a little faster. Hence, I would like to lower the motor rpm, what do you think?

Matt
 
This all depends on how strong your 2F is. That blue rig I posted above had skinny 33's and 3.70's. I could go as fast as I dared on the highway. Plenty of power.

The same rig is now running 36x14.50's with 4.11's. I can still cruise at 70-75 on the highway.

If you want to play with tire sizes and gear ratios, go to the technical section of www.lslc.org and use the calculators.
 
both my 82's run the 33x9.5 with stock 3.70's......both got plenty of power, I never have to go down to 3rd on hills.......she just keep going(and I can even accellerate). I have no disire or need to regear for how I use my 40's. I did regear(to 4.11's) my fj60 after I went to 33x10.5's but the 60 is alot heavier than the 40's....
 
That is true on the strength of your 2F, but mine was rebuilt top and bottom with a rebuilt carb, it was in good shape. What I notced was the pedal response and the hill climbing. The cruiser would run 33 with 3.70, but it ran 33 with 4.11 better. Better canyon driving, better pedal response. I actually got better gas mileage with the 4.11 because I spent less time in the pedal trying to make it go. I also noticed better crawling ability with 4.11. I have a 79 now with 3.73.

Buckroseau if you would like 3.73's, I would be willing to trade for your 4.11.

Thanks
Scott
 
My friend is running 35" bfg MT's on his 79, with 3.73 gears, and it does great, He has 4" lift, and extended shackles. He ran 33"s with only a conferr shackle lift forever. HTH
Rod
 
My same friend also ran 38"x16.5x15 Gumbo monster mudders on his 3.73 geared 79. Altough he hacked up his fenders to fit them.
 
wow! This has been quite the discussion. I'll throw in my opinion if the rest of you don't mind. Personally if it were my truck with a 2.5" lift and 3.73 gears, I'd go with some 33x12.50's on some 15x8" wheels. Like a few have said, if your motor is in decent shape you'll still have plenty of power. A guy in our club was running some 33x12.50s on his SOA FJ60 with 3.73 gears for a long time. Never had a problem with power. I ran 33's with 4.11's for several years and loved the setup.

I wouldn't bother with 16" rims. You'll keep your rims longer than you will the tires and if you're like most cruiser owners you'll end up going to a bigger tire eventually. Tires to fit 16" rims are (in most cases) going to be more expensive than the same tire for a 15" rim and the 15"ers are fine. Personally I don't see the point of a 16" rim. If you think you need load carrying capacity...c'mon, how much are you really gonna carry in your short wheelbase truck? One other point to argue for the 15" rim. Cruisers aren't know for their Cadillac like ride, so anytime you can improve the ride quality on a FJ40 I think it's a good thing. By staying with a 15" rim and running a taller tire you will hav more sidewall to absorb bumps in the road and on the trail. I've almost always run about 25psi in my tires on the road. Running a slightly lower pressure will let the tire "squish" over the imperfections on the road or trail. If you run a 235 size metric tire on a 16" rim you'll have a much shorter sidewall and will end up with a slightly harsher ride.

Once again, my vote is for some 33's. Not only do I think they look the best on a FJ40 with a small lift, but I think they will allow for the most versatility. They'll be fine on the road and since you said you plan on using your truck for hunting and fishing, the 33's will give you a bit more ground clearance which can be nice when you trying to get through some mud or over some rocks to your favorite hunting spot.


I would get the 33's and if you think the power loss is too great, you can rear-gear your diffs at that point. Re-gearing can be very simple. The simplest way would be to find some 4.11 geared complete third-members from a salvage yard or from someone doing an axle swap or something. You could pull the complete third-member and bolt them into your truck and be back on the road in about an hour. Doesn't get much simpler than that, and you don't have to mess with pulling the whole diff apart and setting up new gears.


The only potential downside I can see to running a 33x12.50 is that they might be slightly harder to turn without power steering since they have a wider footprint. When your moving, you probably won't notice much difficulty in turning at all, but if you're stopped and trying to turn the wheel it will probably be a noticeable difference.


To further argue my case for the 33's in this particular case, here's couple pics of FJ40's both with 2.5" OME lifts and 33x12.50s. Not sure who owns the green one but it's a fine looking truck if you ask me. The second picture is Tien Do's super clean FJ40. His isn't too ugly either. :flipoff2:
 
Here's the picture of Tien's 40
 
I know we're talking about a specific situation here and one individual truck, but if we're talking about the bigger picture and what opinions are for the best all around tire size, then my vote is going to be for a 37".

Granted, running a tire this size demands power steering so I won't recommend it to you guys running stock steering. I started with 31's on my truck then went to 33's and then to 35's and ran each of those for a few years each. I've had the 37's for about two years now and I've gotta say that they're definitely my favorite. They're big enough to feel comfortable taking them on any difficulty of trail and still not so big that you can't manage them on the road. I still drive my FJ40 60+ miles each day on the highway and it's awesome to drive. 4.11 gears are ok with a tire this size but 4.88's are MUCH nicer.

So, basically, I think a 37 is the perfect size tire for a FJ40. :)
 
I've been running several sets of 35x15x15 tires for 8 years on my stock 3.73's with little problems. It accelerates very quickly for what it is. Only time I wish I had 4.11's is up the mountain passes through West Va with hard top on and packed full of X-mas stuff heading to Ct to visit family. 3rd gear got lots of use then, but around town I do fine. I vote 33x12.5's all day. MTR's or Geolander MT's would be my choice.
 
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