New Jeep Owner Questions

lrb6805

Die Living
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Grapevine, TX, United States
So I have had my 2006 Wrangler Unlimited (Auto, 80K miles) for about 10 Days now. I've taken it to an off-road shop to have them give it a look over (Dallas Off-Road). They said it looks good and is pretty clean and I'm having them do all fluids/grease in the near future. They did find that I have a 2" budget lift on it but with stock springs

Some things I've noticed so far with my Jeep. I recently drove to Austin and I only got 9-10mpg on highway there and back using cruise control going about 70-75mph. I have 33inch tires and I've noticed my speed is really off from the speedometer. I'll be going 68mph (according to waze) and my speedometer shows 60mph. Also, going 65 mph my rpms are only 1750rpms.

Looking at all of this, is this normal? It seems really off and the gas mileage is really low. I know It's driving a brick down the road, but the shop was saying 13-14mpgs is normal and 9-10 is low.

Am I in need of a regear? Is there anything I can do with the speedometer to make it more accurate? Or is this all normal
 
33s and an auto with overdrive i would do 513s unless its 44s feont and rear the 538s

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With the 33" tires, your speedometer is definitely off. That can be fixed with a new speedo gear with the correct amount of teeth. Your rpms are low also due to the larger tires. The 42RLE and 33" tires is not a good mix if you want even close to stock performance. 4.88 is minimum, and 5.13 is better for that transmission and tire size combination. Chances are your LJ has 3.73 gearing in the axles.

As far as the mileage, are you figuring based on the odometer (which will also be off) or actual miles traveled (odometer reading x % it is off)?
 
So I have had my 2006 Wrangler Unlimited (Auto, 80K miles) for about 10 Days now. I've taken it to an off-road shop to have them give it a look over (Dallas Off-Road). They said it looks good and is pretty clean and I'm having them do all fluids/grease in the near future. They did find that I have a 2" budget lift on it but with stock springs

Some things I've noticed so far with my Jeep. I recently drove to Austin and I only got 9-10mpg on highway there and back using cruise control going about 70-75mph. I have 33inch tires and I've noticed my speed is really off from the speedometer. I'll be going 68mph (according to waze) and my speedometer shows 60mph. Also, going 65 mph my rpms are only 1750rpms.

Looking at all of this, is this normal? It seems really off and the gas mileage is really low. I know It's driving a brick down the road, but the shop was saying 13-14mpgs is normal and 9-10 is low.

Am I in need of a regear? Is there anything I can do with the speedometer to make it more accurate? Or is this all normal

In addition to installing the correct speedo gear disabling OD on the highway will make a huge difference. I have 2005 Automatic with 33s and 42RLE and while 5.13 gearing is ideal with OD disabled 3.73 is nowhere near as bad as I was expecting going from 31s to 33s. And I am not talking about MPG, I am talking about acceleration and being closer to the optimal power band. With OD disabled you will spend way more time in the 2200-2400 RPM range.
 
With the 33" tires, your speedometer is definitely off. That can be fixed with a new speedo gear with the correct amount of teeth. Your rpms are low also due to the larger tires. The 42RLE and 33" tires is not a good mix if you want even close to stock performance. 4.88 is minimum, and 5.13 is better for that transmission and tire size combination. Chances are your LJ has 3.73 gearing in the axles.

As far as the mileage, are you figuring based on the odometer (which will also be off) or actual miles traveled (odometer reading x % it is off)?
I was figuring it based on the odometer

What would the difference between doing 4.88 vs 5.13 be?
 
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Check your gas mileage with the OD OFF.

3.73 is not a bad ratio until you kick in the 0.69 OD. Which gives you a 2.57. Even 4.88 thru 0.69OD is a final of 3.37.
 
I was figuring it based on the odometer

What would the difference between doing 4.88 vs 5.13 be?
Say you bought your LJ new off the showroom floor, and tooled around with the 30" tires and 3.73 axle ratio; life was good, Jeep performed as designed, got the best mpg it could for a rolling brick. Then the coolness factor wears off, new tires would help restore that. 33" would look good, let's go with that! There goes that stock performance. Sure, you can do it, and many do, but optimally, it needs help to overcome the larger tires. 4.88 works for most situations, but if you want that extra to be able to pass on the highway when you need to, 5.13 would be better. If you don't ever go on the highway, 4.88 would probably do the trick. It's that blasted .69 overdrive.
 
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Hey i bought my jeep the same way. 2" puck lift on 33s with some quick sway bar disconnects were the only mods it had.
After recently regearing, I highly recommend doing so if you have stock gears. They're not bad, but like me, you might not know what you're missing.
As to the speedometer, you just need to replace the Speedo gear, which is easy to do. Here's a chart to help you find the right one for you.
https://wranglertjforum.com/threads/speedo-gear-change.83/
Also,
Swap that puck lift out for a 2" BDS lift and you won't be disappointed in the increased ride quality. Doesn't cost much and won't require further modification either.
 
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A gear swap would definitely improve things. 4.88 minimum, 5.13 would be optimum.

If you plan on doing that you can hold off on a speedo gear swap until the gear swap is done.

The other issue is 33's and those spacers. You really need 3.5-4" of lift to clear 33's.
 
A gear swap would definitely improve things. 4.88 minimum, 5.13 would be optimum.

If you plan on doing that you can hold off on a speedo gear swap until the gear swap is done.

The other issue is 33's and those spacers. You really need 3.5-4" of lift to clear 33's.

They guy at the shop was recommending a 3" suspension lift. Would that be enough?


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They guy at the shop was recommending a 3" suspension lift. Would that be enough?
3" is enough for 33's for mall crawling but not for any offroading where you'd want 4" of clearance. You can achieve that with a 3" suspension lift plus a 1" body lift which would be less expensive and easier to get working without vibrations than a 4" suspension lift would.
 
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I get by pretty good with my 2" and 33s. Some occasional fender flare rub at full stuff, but those will be replaced anyway. If you go any higher you need a sye and drive shafts.
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Alright so I talked to my local shop and they price quoted me $1500 flat to change my gear ratio from stock to 5.13.

Includes all parts and labor. They do a 1 year warranty on the pinion/seals and a lifetime warranty on the other parts. They use all Yukon parts.

Is this a good deal or at least a normal price for what they are offering?


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Alright so I talked to my local shop and they price quoted me $1500 flat to change my gear ratio from stock to 5.13.

Includes all parts and labor. They do a 1 year warranty on the pinion/seals and a lifetime warranty on the other parts. They use all Yukon parts.

Is this a good deal or at least a normal price for what they are offering?


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Sounds like a decent deal. Did they give you a break down of parts and labor?
 
Turing off the Overdrive has definitely helped with the RPMs. Is continuing to turn off the O/D a good substitute to regearing or is it a less than optimal solution?

Also, if I decide to do an Aussie locker in the future, is it still recommended to install it the same time as a regear or does it not matter anymore (and just install it myself whenever)?



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Turing off the Overdrive has definitely helped with the RPMs. Is continuing to turn off the O/D a good substitute to regearing or is it a less than optimal solution?

Also, if I decide to do an Aussie locker in the future, is it still recommended to install it the same time as a regear or does it not matter anymore (and just install it myself whenever)?



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Turning off the OD is a temp solution. The Aussie can go in at any time.