31's or 33's 3.55 with NV3550

I have tried different search variables for this question, but didn't find much....

I am entertaining the thought of putting a NV3550 in place of my AW4 in my 98. Details of the actual swap aside, how does a NV3550 and 3.55's do with 31's (I have now)? How about 33's (33x10.5's maybe)?
Some quick math got me this:
3.55 and 31's = 3.09 effective (.46 diff), need 4.07 (.52 diff)
3.07 and 31's = 2.67 effective (.40 diff), need 3.52 (.42 diff)
3.07 and 33's = 2.51 effective (.56 diff)

So, it would seem that this setup would be close to stock with 31's? Since I am ok with the 31/3.55 performance, Would 33/3.07 be close to the same performance?? From what I have read 3.07 wasn't ideal to begin with, so 33's would suck with 3.55's?

Knowing math doesn't equate to reality in this case, I am looking for real world experience.

Thanks,
Mike

Um...you're going in the wrong directon....33/3.07 would be worse than 31/3.55.....WAY worse....

am I missing something or are you really confused?

Yeah, you've got that a bit backwards.

for 31s 3.55s are tolerable.

with 33s you're going to want 4.56 or maybe even 4.88.

I don't think you caught that I am swapping my AW4 for a NV3550. So, I am also gaining a little gear due to my xj having 3.55, over the 3.07's in a xj that came with a stick.

I have and AW4, 3.55's, and 31's now, and I think its tolerable. 31's are few sizes larger than stock. 33's are out of the question for me with AW4/3.55.

So think of it as a XJ with a NV3550 with 3.55's, how would 31's be? How about 33's?

The way I look at it is that an NV3550 with 3.55's would return it to stock running 31's. Next thought is if 31/3.55/NV3550 would be like 27/3.55/AW4, would 33/3.55/NV3550 be like 31/3.55/AW4?

Make sense?

I'd think you would need to know the gear ratios of the NV3550 and factor them into the equation to compare against your current AW4. That's what'll really make the difference. Unless you have a free NV3550 and/or really want a stick shift, it'd probably be a lot easier and more effective to regear your diffs rather than changing your transmission just to get lower gears.

i ran 33's on the auto, went down to 31's until i can afford 4.56's. the 33's are just sittin back there now, but they will go back on

Just use this http://www.grimmjeeper.com/gears.html and all your questions will be answered.

Timber said:

Just use this http://www.grimmjeeper.com/gears.html and all your questions will be answered.

Click to expand...

I used that already, but I will take a closer look, makes sense to look at it gear by gear.... I was looking for feedback from folks who have/had a NV3550 (or ax-15 I guess) with 3.55's.

BlackSport96 said:

I'd think you would need to know the gear ratios of the NV3550 and factor them into the equation to compare against your current AW4. That's what'll really make the difference. Unless you have a free NV3550 and/or really want a stick shift, it'd probably be a lot easier and more effective to regear your diffs rather than changing your transmission just to get lower gears.

Click to expand...

I am not changing transmissions to run 33's. I may never run 33's, I was just curious about that. I am (possibly) doing this to get the stick shift, thats the only reason...the 3.55's over 3.07's is a bonus.

All,
I know my inital post might not have been too clear, hopefully the second one explains it better.

I might have the opportunity to swap my aw4 for a nv3550. Since I have 3.55's in mine, it will bring the jeep back to stock with the NV3550/31's. I was just curious if taking it a step further, and going to 33's with the NV3550/3.55's would give the same performance as my current 31's with aw4/3.55's.

I may be way off base comparing in this fashion, thats why I asked for the real world experience.

I really do appreciate the comments so far. Thanks again.

fordtech said:

I used that already, but I will take a closer look, makes sense to look at it gear by gear.... I was looking for feedback from folks who have/had a NV3550 (or ax-15 I guess) with 3.55's.

Click to expand...

Once I played with this a little closely, this tells a totally different story then the gear calculators.

Looks like a NV/3.55/31 turns about the same in OD/5 as AW4/3.55/31....1961 vs. 2014 respectively. I thought I would see the NV turn higher RPM due to the change from 3.07 to 3.55.

Looks like even with 33's the NV is in good shape, you would just delay 5th and be shifting between 4 and 5 alot?

So they really cripple 5sp jeeps with 3.07's (?) Should they have used 3.55's on the 5sp jeeps?

Thanks for making me revisit this site Timber. Still would like feedback from folks who have/had this!

I run 3.55's with 33x12.5 15's with an ax 15 it is a good deal better than the 3.07's but i,m still going to go with 4.88's.My ratio now is tolerable but could be better.But so could my money situation.It's a good idea I like clutched vehicles better more of the driveing experiance.

JACK

No problem. I was thrilled once I first found it a couple years ago--I really learned a lot just by playing around with it.

1sickhick said:

I run 3.55's with 33x12.5 15's with an ax 15 it is a good deal better than the 3.07's but i,m still going to go with 4.88's.My ratio now is tolerable but could be better.But so could my money situation.It's a good idea I like clutched vehicles better more of the driveing experiance.

JACK

Click to expand...

Using the different calculators would make you think that the NV/3.55/33 combo would perform comparable to the AW4/3.55/31 combo....

If I do this, I probably will stick with 31's anyways, at least until it isn't my daily driver anymore.