YJ doesnt climb hills

S

south7069

New member
i just rebulided the I6 bored .060 with high enegery cam, borla header plus cat back, motorcraft 2150 non smog, tfi conversion, nutter bypass, and every emission thing and all them vac lines have been removed it runs great on flat land just when that big hill comes at 70 mph i have to down shift to 4th then sometimes i have to go to 3rd anybody have a clue?
 

Likely a gearing issue, guessing you still have the 3.07 axle gears that came stock?
 
Sound like a jeep thing to me(my jeep has a 5th gear??)

Its bad when you can run 80 in 3rd and your passing gear is 2nd hahaha
 
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To give you some perspective on the importance of proper axle gearing, my Jeep's 2.5L 4banger on 35" tires will climb highway hills very well with the 5.38 axle gears. I seldom have to downshift from 5th but for the steepest grades.
 
im pretty sure it has stock gears havent had any money after the rebuild to open the axles up to find out i just bought it not to long ago so if it is stock should i go with a 4.11 or 4.56 or what? its dana 30 and 35 by the way you army bounty hunter
 
Hope this helps...
Yellow - highway driving, good fuel economy
Green - Daily driver, best overall performance
Blue - Most power and towing, reduced fuel economy.
 

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Man, what kinda hills you talkin' about in Ponchatoula??:shock::shock: The only hills I've see around there were on-ramps!:lol::lol:

Anyway, like others have said, gearing will help tons!! And if you need a spare fifth gear, I've got one with very, very little use!
 
south7069 said:
........and mud4feet im in the ozark mountians bubba
Click to expand...

Hey, man, sorry!!! I just saw your sign-in stuff where you were from Ponchatoula!:shock: Go by there every time I go to NOL! You understand, of course. Now, the ozarks, I can understand! :shades:

bubba mud
 

How does one figure out the gear ratio? I have none of the original paperwork, or owners manual (as if that would do much good).
Very helpful chart iraq vet
 
mud4feet said:
Hey, man, sorry!!! I just saw your sign-in stuff where you were from Ponchatoula!:shock: Go by there every time I go to NOL! You understand, of course. Now, the ozarks, I can understand! :shades:

bubba mud
Click to expand...


yea im from there just moved up here about a month ago
 
dzman49 said:
How does one figure out the gear ratio? I have none of the original paperwork, or owners manual (as if that would do much good).
Very helpful chart iraq vet
Click to expand...
There should be a tag bolted to the diff cover on both the front and rear that has the gear ratio stamped into it. If it's not there you can put the jeep on jacks and rotate the tire, counting how many turns the driveshaft makes for one revolution of the tire.
 

I thought there might be something like that. I'll check the next time I have it off the ground. Thanks.
 
iraq_vet_x2 said:
Hope this helps...
Yellow - highway driving, good fuel economy
Green - Daily driver, best overall performance
Blue - Most power and towing, reduced fuel economy.
Click to expand...

If you have a 4-banger, you are want to look into the last blue number for the correct gear... I have 4.88 and 33's on my 2.5L, and I am kind of wishing I could go to 5.13 or something, but that means 2 new axles (plus lockers!), so it's out of th plan for some time!
 

I would stick in the blue range on that chart regardless of engine type. It helps to go a little lower than recommended as the chart only takes into account the added tire size and not the weight, it robs more power to get the heavier tires moving.

I would look up the rpm for the stock axle ratio and tire size, then go down to the tire size you would like to run. Move to the right until you find a similar rpm, then move a box or two more to the right for best performance.
 
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