Changing rear ends in a Wrangler 4.11 >>> 3.07?

My reading of the Jeep WebSite says that the base Wrangler with four
cylinder engine is available only with a 4.11 rear end, while the
inline six comes with a 3.07.

I'm considering a Wrangler as a boat car -- to be loaded aboard a
yacht rather than having to rent cars -- so weight and size are an
issue. I've owned a CJ5 and a bunch of other 4x4 vehicles.

How much would it cost to swap out the two 4.11s for 3.07s? I don't
need a slow crawl, but would like to keep the revs down at 65 and,
presumably, get better fuel economy.


Thanks,

Jim Woodward
and here's the boat, for anyone interested >>> www.mvFintry.com

Likely just the labor.

Most folks want to swap the other way to accommodate larger tires and
would be more than glad to ship you their old 3.07's and pay the
shipping back on your 4.11's for a swap.

My 86 CJ7 258 straight six and T-5 tranny came with 3.31's

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Jim Woodward wrote:
>
> My reading of the Jeep WebSite says that the base Wrangler with four
> cylinder engine is available only with a 4.11 rear end, while the
> inline six comes with a 3.07.
>
> I'm considering a Wrangler as a boat car -- to be loaded aboard a
> yacht rather than having to rent cars -- so weight and size are an
> issue. I've owned a CJ5 and a bunch of other 4x4 vehicles.
>
> How much would it cost to swap out the two 4.11s for 3.07s? I don't
> need a slow crawl, but would like to keep the revs down at 65 and,
> presumably, get better fuel economy.
>
> Thanks,
>
> Jim Woodward
> and here's the boat, for anyone interested >>> www.mvFintry.com

Oh and as a side note, lower revs on the highway in a Jeep CJ or
Wrangler do not normally mean better gas mileage!

The thing has the aerodynamics of a brick and it takes power to push
them through the air.

That is why the 4 banger gets about the same mileage as the 6. The 6
doesn't have to work as hard.

I have 3.31 gears with my 258 with the T5 tranny turning 33x9.5 BFG
muds.

If I run at 65-70 mph in 5th gear, I am only turning 1750-1800 rpm. It
still has lots of pull, but I need almost all the gas pedal travel to
compensate for wind or a slight hill.

If I keep her in 4th, I am turning 2300 rpm and only need a twitch on
the gas pedal for the same wind/slope compensation.

Keeping it in 4th gives me a sweet 19 US mpg, or 11 L/100 km use 5th and
I drop way below 15 mpg on the same trip. (we run for about 300 km to
get to our off road place)

My speedo and odo are GPS certified right on with my tires, and I am
quite happy with my mileage.

If I bought the 4 banger and expected to get 65 mph out of it, I for
sure would keep the 411's, or I would for sure do some good mileage
checking first.

I don't think any flavor of 'Wrangler' or CJ can do much better than a
'real' 20 US mpg running at 65-70 mph. Now maybe if you put a diesel in
it....

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Jim Woodward wrote:
>
> My reading of the Jeep WebSite says that the base Wrangler with four
> cylinder engine is available only with a 4.11 rear end, while the
> inline six comes with a 3.07.
>
> I'm considering a Wrangler as a boat car -- to be loaded aboard a
> yacht rather than having to rent cars -- so weight and size are an
> issue. I've owned a CJ5 and a bunch of other 4x4 vehicles.
>
> How much would it cost to swap out the two 4.11s for 3.07s? I don't
> need a slow crawl, but would like to keep the revs down at 65 and,
> presumably, get better fuel economy.
>
> Thanks,
>
> Jim Woodward
> and here's the boat, for anyone interested >>> www.mvFintry.com

You 'really' don't want to go from a 4.11 to a 3.07... you would lose so
much power that your Jeep would seem like the most sluggish vehicle you've
ever driven.

Jerry
--
Jerry Bransford
To email, remove 'me' from my email address
KC6TAY, PP-ASEL
See the Geezer Jeep at
http://members.cox.net/jerrypb/

"Jim Woodward" <[email protected]> wrote in message
news:[email protected]...
> My reading of the Jeep WebSite says that the base Wrangler with four
> cylinder engine is available only with a 4.11 rear end, while the
> inline six comes with a 3.07.
>
> I'm considering a Wrangler as a boat car -- to be loaded aboard a
> yacht rather than having to rent cars -- so weight and size are an
> issue. I've owned a CJ5 and a bunch of other 4x4 vehicles.
>
> How much would it cost to swap out the two 4.11s for 3.07s? I don't
> need a slow crawl, but would like to keep the revs down at 65 and,
> presumably, get better fuel economy.
>
>
> Thanks,
>
> Jim Woodward
> and here's the boat, for anyone interested >>> www.mvFintry.com