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Discussion Starter #1
2007 jeep wrangler 6 speed

I was wondering how 35s would work on 3.21 stock gears. Right now i have 285/75/16 treadwright guard dogs which measure out to 33.2 and 315 in a non retread tire normally measures out to 34.2?(so only an inch difference). Im also running black rock type d rims which are 37 lbs. So my question is if i went to alloy rims which i assume i could easily drop 10 lbs and went to a factory tire which would also drop a ton of wieght(those retreads are heavy).
Anyways im wondering if i would lose a considerable amount of power right now i shift at 2k rpms. Which i dont know if its normal that sounds like a low rpm to shift at with 3.21 gears but i bought this jeep used at a dealership so i have no idea if it was regeared in the past(it came on wrangler sr-a wheels they looked stock and i dont think people buy sr-a's for aftermarket because imo they suck but who knows). As for offroading i live up in nw PA so its just light trails and mud for me. Im also not going to run a lift with these i have 18/60 coils on it now and im going to get flat fenders im trying to keep a low COG since its my DD. I also dont need to go fast i have an aprilia for that but i drive it around 5k miles a year and the fastest roads around here are about 60 mph anywhere thats more than an hour away i take the car.
 

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You're not gonna like it. Mpg will crash and it'll be pretty sluggish.
 

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Since you have heavy wheels and heavy tires, if you went to a light 35 you would probably maintain the same level of acceleration. The lightest 35 on the market, to the best of my knowledge is the BFG AT in size 35/12.5/15 at 50lbs if you throw on light alloys you can keep the weight down. I believe when I checked the 285 guard dogs are about 65 or 72lbs a piece. So drop 15-22lbs on each tire and another 10-20 on each wheel and you will probably accelerate a bit better. 35's aren't that much bigger than retreaded 33's and 25-42lbs a corner is a ton to drop in weight. Not to mention less rolling resistance of those ATs
 

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Discussion Starter #4
Wierd thing is i was running 265 duratracs on stock steel wheels pulling 14 mpg avg now im pulling 15 with heavier rims and way heavier tires. 25-42 lbs at the wheel is ALOT to drop too.
 

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I ran 35's on 3.73 gears for a year (3.8 with 6sp and relatively light GY MTR's). I now have 4.88 gears and the difference is amazing. I would never want to go back. Even at low altitude in flatland Florida it was a dog, and I don't drive fast.
 

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I ran 35's on 3.73 gears for a year (3.8 with 6sp and relatively light GY MTR's). I now have 4.88 gears and the difference is amazing. I would never want to go back. Even at low altitude in flatland Florida it was a dog, and I don't drive fast.
Yes but the pedestal and the 3.8l is a big difference as in the 3.6 you only need 4.10 to 4.45 and I have 4.10 and it drives pretty good
 

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Discussion Starter #11
Im ok with the sluggish speed right now i was just wondering if i dropped wieght going to alloys and a lighter tire would it stay the same or if id gain acceleration.
 

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Discussion Starter #13
but if i dropped wieght per tire and rim that would compensate for the size? As said earlier 25-42 lbs per tire/rim
 

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It would work but eventually you'll want to reagent, what I say to most people is buy the tire drive it if you don't like it wait and you can rea-gear if you like it we'll you like. It's really up to you if your satisfied with the performance. :)
 

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If you don't have hills or mountains where you are, and you can tolerate sluggish acceleration, you can get by with it for awhile as I did. Your mpg will suffer and you'll put more stress on your clutch. It's also not ideal for going off-road.

You can always wait to see what it's like, but you might want to budget for a regear at your earliest opportunity. I regained the use of my 5th and 6th gears that I rarely used when I had 3.73.
 

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Im ok with the sluggish speed right now i was just wondering if i dropped wieght going to alloys and a lighter tire would it stay the same or if id gain acceleration.
You wouldn't lose any acceleration if you go as light as possible. If you decide you like a heavy mud tire then you will lose acceleration. It would be all about losing as much weight as possible. The benefit of the BFG ATs is that they last a long time, not a bad tire, and are super light. Only a pound heavier than the duratrac in the 33/12.5/15 size
The weight isn't the problem it's the size of the tire that puts more stress on the engine and weight of the tire
The weight is a big part of the problem. It's actually just as big as the size itself. The tires inertia is based on the radius times the integral of the weight so weight is a big factor. Retreads are bigger than normal tires so at 33.5 he is running a very large 33. A standard "35" never measures more than 34.5 so his radius is going up by 1/2 an inch or about 3% but if he drops the weight by what I quoted originally that's about a 20-40% weight reduction. That is huge compared to the slight size increase. You wouldn't even notice the small size difference with that kind of weight loss.

OP if you're happy with your current state of acceleration then it won't be worse. Eventually you may like a regear but light 35's won't be as bad as you're super heavy 33's
 

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Don't discount the size of the tire making a big difference. It's really the 'final gear' and size does matter (that's what she said). A 35 tire that runs small may help.
 

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Iv been riding on 35" bfgs with 6 speed on my 09 jk x and 3.21 gears...I can still drive 70 in 6th gear. Shes slower to get there but its a jeep not a racecar.
 

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You're running heavy retreads and heavy rims. I doubt you would notice much difference with tires an inch taller.
 
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