Topic: Its so nice when....

[flyingbrick]

Ya, I find sometimes when I use low..its too low sometimes for hill climbing so I put it in high and first gear, pick up some speed (nothing to crazy) and it works, I make it up the hill...most of the time.   What do you guys suggest on high climbs with a 4cyl? How do you tackle a hill? lol

5th & low is about equal to first & high, play with the gearing you'll find what you need for hills, or so i have found.

[95yjman]

Really? I'll have to play around with it see how everything works..

[jcsanders79]

Ya, I find sometimes when I use low..its too low sometimes for hill climbing so I put it in high and first gear, pick up some speed (nothing to crazy) and it works, I make it up the hill...most of the time.   What do you guys suggest on high climbs with a 4cyl? How do you tackle a hill? lol

The best way is to have your gears set right so you don't use 4-low until you can't get over it in 4-high.  On rides with lots of hills and mud I leave it in 4-high until I don't have enough torque to get over something.  Got 4.88 gears and 33" tires this is real close but on the long and steep hills I wish I had a little more torque.  I could use 5.38 and 33" or 35" tires for optimal 4-high and then low I will use for crawling.

[jfrabat]

5th & low is about equal to first & high, play with the gearing you'll find what you need for hills, or so i have found.

Assuming the standard AX5 gear reatios (according to the Jeep service maual), and a 2.72 NP231 TC (as stamped in mine), the ratios are:

1st w/4L    10.69
2nd w/4L    6.34
3rd w/4L    3.94
4th w/4L    2.72
5th w/4L    2.31
Rev w/4L    12.89

1st w/4H    3.93
2nd w/4H    2.33
3rd w/4H    1.45
4th w/4H    1.00
5th w/4H    0.85
Rev w/4H    4.74

So, 5th on low is basically equal to 2nd in high...  4th on low is a little less than 1st on high (it's like an in-between 1st and 2nd in high).  3rd gear on Low is about the same 1st gear on high.

So if you dont plan to get past 2nd gear in 4H, you may as well drop to 4L and start out in 2nd or 3rd gear, and work your way up to 5th (if the hill allows).

Felipe

[95yjman]

Sweet info guys! I know some guys are hardcore on 4 low and others switch back and forth...

[chardrc]

we always use 4lo for the mud.. nice to be able to down shift for more power.

[brian674]

4lo for mud?   Don't you want wheel speed for mud?

[DodgeMudder]

Only time I run 4hi off road is if I need good wheel speed to back out of some mud, otherwise I just use a higher gear in 4lo.  It jut makes it easier to control what your doing with out needing as much slippage of the clutch.  I run a little of everything off road except sand and dry rocks as there are known around here.

[jfrabat]

4lo for mud?   Don't you want wheel speed for mud?

If you look at the ratios, you can get the same wheel speed in 5th lo as you would in 2nd hi...  And with the 4 banger, I doubt you would get past second in mud.

[brian674]

I'm not arguing, just never considered using that approach.

Actually this reminds me of an argument I had with a friend at work. I was discussing axles and 4lo and 4hi among other people. I said to the guys I was talking to, that I didn't use 4lo in any situation except where I needed good torque. I then went into the usefulness of a locking diff.

This guys piped up and said, Well, that is why you need 4lo because on Jeeps when you use 4lo the diffs lock and all for wheels spin.

I had, of course, some inside knowledge that this was not the case. I'm sure you all know that a standard d35/d30 stock set up is open diff limited slip...and how that all works.

Well this guy went on to say that 4lo has a viscous coupling blah blah blah. Needless to say he thought he knew what he was talking about and I couldn't convince him otherwise because he said his brother was a Jeep mechanic.

So, how many of you use 4lo all the time off road? I only use it when I need it, personally. Is there any danger of using 4lo beyond a certain gear or MPH/speed? I thought I read somewhere not to use 4lo more that 30 MPH and not to use 4hi more that 55 MPH, does that sound true to anyone?

[Mozman68]

I don't think it hurts to use either....4-lo is nothing more than a different gearing ration, so you shouldn't run it at any speed higher than you normally would exceed the recommended max level on the RPM band in 5th gear...not sure what speed that is as I have never been in 4-lo in 5th gear.

4-hi can be run at any speed...you just should not shift into it at a speed higher than 55 mph.  Of course, again, I've never found myself in the position to be using 4wd over 50 mph anyway.

[jfrabat]

This guys piped up and said, Well, that is why you need 4lo because on Jeeps when you use 4lo the diffs lock and all for wheels spin.

I had, of course, some inside knowledge that this was not the case. I'm sure you all know that a standard d35/d30 stock set up is open diff limited slip...and how that all works.

Stock d30 and d35 on a Jeep are open diffs; they dont even come with limited slip, they are just plain old open, meaning that if one wheel of each axle looses grip, you are not going anywhere.

Well this guy went on to say that 4lo has a viscous coupling blah blah blah. Needless to say he thought he knew what he was talking about and I couldn't convince him otherwise because he said his brother was a Jeep mechanic.

I would not take my Jeep to his brother!

So, how many of you use 4lo all the time off road? I only use it when I need it, personally.

I dont use 4lo ALL the time, but I do put it on before I go into an obstacle that MAY require it (if you shift from 4hi to 4 lo in the middle of the obstacle, you lost momentum and odds are you will be stuck as a result).  But most of the time, for the type of trails in Panama, 4hi is enough.  We ussually keep 4lo for mud pits and river crossings.

Is there any danger of using 4lo beyond a certain gear or MPH/speed? I thought I read somewhere not to use 4lo more that 30 MPH and not to use 4hi more that 55 MPH, does that sound true to anyone?

4lo I think it was 20 or 30 mph, dont remember which (but should be on the reverse side of your shade).  I have not heard anything about 4hi, but if you are doing more than 55mph, you probably should not be in 4wd anyway!

[chardrc]

4lo for mud?   Don't you want wheel speed for mud?

to put it in context most of my off roading is in my grandpas cj2a that starts with 60hp so you are always low on power.... so we always go in low other wise we wont have enough power..+ when you have enough traction you don't need as much speed.

[Mozman68]

btw...I've only really used 4-lo when I come up to hill that I know I will have to down shift on if I was in 4-hi.

[neale_rs]

I use 4 lo all the time.  We get rock obstacles often enough on the trails that it would be a pain to be switching back and forth between 4 lo and 4 hi. On the easy stretches, sometimes I cruise in 4 lo and 4th or 5th with top speed being about 20 mph.