New jeep owner!

[jeeprookie]

RE: throttle body size

I think im going to buy a '99 wrangler 6cyl. auto. Im happy to join the Jeep family. Ive owned Toyotas, a Chevy and a Ford so I look forward to the unique change of owning a jeep.
My first question for you all is basic. I want to put on 33x12.5's.
Do I need a 3" or a 4" suspension lift? I see that many people are running a 4" but I just want to make sure.
Question 2: will my gas mileage and power drop significantly with the 33's?
Thanks and once again im glad to be here!

 

[Sully]

Hey, welcome to jeepz! You came to the right place.

A 3 inch suspension lift will fit 33 inch tires no problem. There should be a noticable change in gas mileage and power. The larger tires slow it down a bit. This can be fixed by regearing. Nice move on getting the 6, it will push the 33's on stock gears with no problem.

 

[jps4jeep]

depends. you can safely run 33's on a TJ with a 2" budget boost and a 1" body lift, or a 3" suspension lift. You can run a 4" this will allow for a little more flex and ground clearence, but not totally needed.

as for milage and power, power will drop significantly! you could have anywhere from 3.54 gears up to 4.11's... so with 33's on a 6cy auto tj, 4.56 and Numerically higher (lower gears) would be Ideal. Milage wise, knowing that florida is basically a huge flat piece of land as opposed to Massachusetts where it is all hills, you should get better milage with stock gears and 33" tires. why... in 4th gear, in stock form, you would travel at 2100 rpm's at 65mph (I am guessing on all numbers) with stock gears and 33's, you will be at 1500 rpm's. but gains will only be significant on high ways. around town, it is a different situation... there are things like added weight of the tires to get spinning from a stop, weight of the equipment you added.

 

[jeeprookie]

Thanks for the input! Im trying to stay away from regearing (strictly for the fact of cost). Maybe ill do the 33's a 4" lift and add some performance mods to help with power.

 

[Tug-n-pull]

Abandon All Hope Young Jeeper! tug heheheh

 

[Bounty__Hunter]

RE: Jeep vs. Hummer.

Many 4.0L Wrangles came with 3.07 axle gears, which really suck with 33" tires even with the 4.0L engine. Check out the jeeps closely, read the tag bolted to each differential cover and hold out for a Wrangler with 3.73 gears. 3.07 and 3.73 are the most common found in 4.0L TJ's.

 

[berettajeep]

4.0 5 speed 3.07:1
4.0 auto 3.55:1
2.5 5 speed 4.11:1
2.5 auto 3.73:1

This is the majority (sp?) of how they come from the factory but double check.

 

[GaryMB]

RE: TFI is it all it is cracked up to be?

3.07:1 r&p with 33's won't be great, but i think you could manage if you had a 4.0L. Definately get the 3.73's with the 4.0L if you have a choice.