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So, if I can fit 35's with my '3 inch' lift (I think it's a little more), other than the speedo, does the fact that I have a Manual and not an Automatic make a difference on if I need to change anything? I hear about regearing, and I assume it's the rear we're talking about, and that it affects shifts. What else is going on? Will I lose torque without changing the rear gears? Don't I have different gears than the autos anyways?

Someone please school me, and thanks.

R

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I'm also curious on rehearing.  At what tire size is this recommended?

Regarding 35's on a 3" lift, I thought you could only get up to 285/70?  Or is this just max tire with 3" lift and no BMC?

I am currently running 33x12.5x17's with a 4.5 offset rim. Dick Cepek MT. Exact specs here: http://www.dickcepek.com/tires.php?item=MudCountry

I did an agreesive BMC and seem to have lots of free space now, even under flex and u-turn, which is why I'm curious. A toyo open country in 35 will be a total of 2" taller (total diameter) and 3/4 inch wider.

You'll want to re-gear with 35's. Doesn't matter if you have a manual or a sludge-a-matic.

I re-geared my HiLux when I went from 31's to 35's, and it made a world of difference.

By changing from a 32" to 35" tire, your effective final drive drops from 3.90 to 3.57.

If you think your FJC gearing/motor/driving style is perfect as it is, then 4.56's are closer to stock.

If you drive at elevation a lot, or tow anything, you'll probably want to go with 4.88's. 

If you have a 4wd FJC, you'll need to change both front and rear gears. 

You will lose effective torque without changing the final drive gears.

Yes, you have a different final drive than an AT FJC. But not that different.

Great info. Thanks Niko.
Any need to regear at 33? What is involved in regearing?

Not really. The effective final drive ratio goes from 3.90 to 3.78.

But I think Toyota's choice of motor for the FJC is kind of dumb (IMHO, it should have the 1HD-FTE direct-injected turbo-Diesel), so if it was me (and I had come across a bag of money), I'd change to a 4.10, just for general drivability.

Regearing involves changing the ring and pinion gears, bearings, seals, etc. (usually as a kit). Figure $900+ depending upon what parts and who you choose to do the work. You can do it yourself, but I wouldn't.

If the final drive ratio goes down, why do I get less gas mileage? Shouldn't I get better since 4.10's should rev higher, hence less mileage?

DId I miss something?

The gears (transmission, transfer case, final drive) are just multipliers used to keep your vehicle's powerband optimized for maximum power and/or efficiency. If your final-drive gearing is too tall, your engine has to work harder to do the same work. Working harder means your foot is further to the floor which means the engine's fuel injectors are squirting more fuel into the engine than would be necessary if the engine's RPM were optimized for the load encountered.

Think about climbing a steep hill at elevation in 6th gear. Foot to the floor, not going all that fast, engine struggling. Same thing.

If you are going to regear, you may also want to look into getting a front locker as well. That's what I plan on doing if/when I regear. saves money on labor by having them swap that in while its opened up.

If you are going to regear and get a locker, might as well go to SFA while you are at it!
I am running 35x12.5 KM2's on a 3" Procomp lift. I have a 6MT.. Did an aggressive BMC, but the problem I ran into was the tire hitting the pinch weld at almost full turn. I had a 1.5" body lift sitting in the garage for 2 years and was debating on putting it on. Just in case I ordered LR UCA's to get my alignment into spec and also push the tire forward.. After putting on the body lift, it is now clearing everything (for street driving), but for offload I think it will still hit the BMC. Hoping the UCA's will help with that issue (still sitting in a box). In regards to acceleration and mpg (especially my setup is heavy), mpg takes a major hit. But, as a reference for performance, I was able to go over the Grapevine in 5th gear just fine and still able to accelerate. I am also able to go over the Sunol grade in 6th gear if I maintain 65mph minimum. If I bump into a slower car, then I have to shift into 5th. Of course, towing will be another issue. Regearing is something in the future (not a priority to me), but wanted to chime in and share my experience thus far.

Thanks David. This is great, real-life, information. 

I was just on the Sunol Grade, after I read your message, and on my 33's I'm getting about the same experience. 

I will have to think on this one for awhile. I probably have a few more months on these tires, then its decision time. 

Thanks!

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