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mpg's

Highlights Only
My CJ5 is good for about 12 , down hill, with a tail wind, in the southern parts of the united states, on a good day with a fresh tune.:cool:
 
I keep a record in the CJ, but off the top of my head, No lower than 18, high of 28, usually sits around mid 20's for a highway average.
 
coldwater said:
I keep a record in the CJ, but off the top of my head, No lower than 18, high of 28, usually sits around mid 20's for a highway average.
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If you have a stock AMC 258 i6 / 4.2l or Iron Duke 4 banger I call BS on that one. In 19 years of ownership the only people I have ever met to get those kind of numbers had swapped over to a Vortec FI V6 motor. My AMC 258 i6 / 4.2l ran like a champ and was always in good tune and the best it did was 18mpg. Post some pics of that log.:bounce:
 
IOPort51 said:
My CJ5 is good for about 12 , down hill, with a tail wind, in the southern parts of the united states, on a good day with a fresh tune.:cool:
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funny stuff.......
same as me (except mine is a CJ7 )
my overall avg is around 9 to 12 mpg :)
 
coldwater said:
I keep a record in the CJ, but off the top of my head, No lower than 18, high of 28, usually sits around mid 20's for a highway average.
Click to expand...


Is that on a straight 20mile run downhill both ways?:laugh:
 
Kane said:
If you have a stock AMC 258 i6 / 4.2l or Iron Duke 4 banger I call BS on that one. In 19 years of ownership the only people I have ever met to get those kind of numbers had swapped over to a Vortec FI V6 motor. My AMC 258 i6 / 4.2l ran like a champ and was always in good tune and the best it did was 18mpg. Post some pics of that log.:bounce:
Click to expand...

1, who said it was stock. 2, call BS if you feel better doing it. 3, I don't really care enough about the subject to have to resort to lying about fuel mileage in a 31 year old jeep. It's sensably geared, has reasonable tires on it, and has a few well placed mods. We're not talking rocket science here, and I didn't claim it got 35 MPG. it hits mid 20's on the highway doing the speed limit, and average around town is around 18. If I felt some compulsion to lie about fuel mileage, I would have come up with better numbers.
 
I used to get 20+mpg. But that was in a Flat Fender Willis with a 2300cc Pinto motor.;)
 
I don't fell so bad now, Im getting 10 with a V8 :D
 
When I first got my 79 CJ7 I got 17mpg. Then I touched the carb. (Carter BBD) Adjusted the Carter the best in could, (Fixing to Go with a 32/36 Weber)
The best I've gotten with the Carter BBD now is 12 - 15. More like 13 mpg. I'm running AMC 258 i6 / 4.2l , stock gearing T-150 Transmission and 10.5x15 mud and this is NO BS!
Good Luck with your wheeling...Wilurb
In 1979 a friend of mine I was stationed with purchased (Off the Showroom) a 1979
CJ5 . Bone Stock he was getting 15 to 20. That was after he had abut 3000 miles on the new stock Jeep
 
My J-10 gets 19 and 21 if I drive right and it has a AMC 258 i6 / 4.2l , T-176 with the 2.73 axle.
so the only difference is the gear ratio as far as I can see.
so what is the axle ratio in the scrambler??:cool:
 
coldwater said:
1, who said it was stock. 2, call BS if you feel better doing it. 3, I don't really care enough about the subject to have to resort to lying about fuel mileage in a 31 year old jeep. It's sensably geared, has reasonable tires on it, and has a few well placed mods. We're not talking rocket science here, and I didn't claim it got 35 MPG. it hits mid 20's on the highway doing the speed limit, and average around town is around 18. If I felt some compulsion to lie about fuel mileage, I would have come up with better numbers.
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I put the bouncy guy in there to show that I am just razzing you. Jeez. relax a bit.
 
IOPort51 said:
My J-10 gets 19 and 21 if I drive right and it has a AMC 258 i6 / 4.2l , T-176 with the 2.73 axle.
so the only difference is the gear ratio as far as I can see.
so what is the axle ratio in the scrambler??:cool:
Click to expand...

Chances are if it's original. They are 2.73. The high altitude option was 3.31.
 
scrambler said:
I honestly don't know what gear ratio I have. I just know I have stock tires, AMC 258 i6 / 4.2l , 4 gear manual Transmission . How would I find out what I have?
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Chances are if it's original. They are 2.73. The high altitude option was 3.31.

If your dying to find out, you can put it up on jackstands. Make a chalk mark on the driveshaft & another on the tire. Rotate the tire & count the rotations on the driveshaft. I.E. 2&3/4 turn is 2.73, 3&1/3 is a 3.31, 3&3/4 a 3.73 & so on. Oh yeah, if you have a open rear double those numbers.;)
​
 
There should be a tag hanging from a bolt on the diff that show tooth counts for the gears to get the axle ratio.
 
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