Re-gear?

rokdaddy

Wheeling
Founding Member
Location
New Mexico
^^^That's a kinda non-specific statement... what type of Dana(s) would you go for? And to stay on topic, which ratio would you go with for your 33's?
 

outlaw_xterra

Bought an X
Well in all honesty you wont need 5.57 with a dana 44. But in my opinion it would be best, to sas with a dana 60 and 14 bolt with 5.13 and 37s would be a great start then tcase upgrade to really torque in4lo
 

DC xterra

Wheeling
Location
CT
i would go with 5.13 for 35', at that size they are around $500 each for the X, you can get a set of dana 44 and the gear upgrade for cheaper than that
 

rokdaddy

Wheeling
Founding Member
Location
New Mexico
Well in all honesty you wont need 5.57 with a dana 44. But in my opinion it would be best, to sas with a dana 60 and 14 bolt with 5.13 and 37s would be a great start then tcase upgrade to really torque in4lo

That does sound like a best case scenario but if I can find a good set of D60's (reasonably priced) they definitely won't be living under the Xterra. Would be a sick setup though.
 

rokdaddy

Wheeling
Founding Member
Location
New Mexico
i would go with 5.13 for 35', at that size they are around $500 each for the X, you can get a set of dana 44 and the gear upgrade for cheaper than that

That's true but most of the D44's that I've seen for under $250 are in need of serious work. I have front and rear D44's off of a late seventies Waggy and even though they're in pretty good shape, it looks like I'll have to put about $1300-$1500 into each of them to get them fully restored and ready to go (with lockers). That doesn't even include the cost of the axles themselves.

I'm not even sure if I want to bother with the rear D44; the H233b is at least as tough as the D44, it's probably tougher. Besides, I already have a 5.14 R&P and air locker for the H233b. The Dana has a lot more aftermarket support though.
 
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DC xterra

Wheeling
Location
CT
yeah lots of them are crap, if it was me i would look for some bronco axles or maybe F150

the H233b are tough as nails just like our stock axles but like you said dana's have a ton of aftermarket parts and upgrades cheaper to , just easier to work with. if i ever consider sas ing my X i would run a D44 front and D60 rear. would never consider upgrading my stock axles with higher gears.
 

rokdaddy

Wheeling
Founding Member
Location
New Mexico
[FONT=&quot]So I hear a lot of folks repeating that 5.13's are "perfect" for 35" tires... how did you come to this conclusion? Why not go lower (within reason) to at least maintain the stock final drive ratio?


-Rok
[/FONT]
 

TKDx00

Lockers Installed
Founding Member
[FONT="]So I hear a lot of folks repeating that 5.13's are "perfect" for 35" tires... how did you come to this conclusion? Why not go lower (within reason) to at least maintain the stock final drive ratio?


-Rok
[/FONT]

Rok...you ask a great question. I was under the impression because of all the comments that 5:13 WAS the correct gearing to do this. Is there a tranny/gearing/Nissan Techie in the house that can put this to bed?
 

rokdaddy

Wheeling
Founding Member
Location
New Mexico
5.14:1 is the mathematically correct ratio for 33” tires if you want to maintain the factory final drive ratio. I’ll re post the formulas again:



new tire diameter * old diff ratio / old tire diameter = New diff ratio


Using this formula with the Nissan specs from the door jamb sticker on my 2000 X suggests that a 33" tire will need a 5.16 gear set to restore the factory final drive ratio:


33" * 4.63 / 29.6" = 5.16


5.142 is the lowest gearing that will fit in our stock diffs and technically speaking, it is a tiny bit less than what is needed to restore the "stock" drive ratio. 35" tires requires a much lower ratio:


35" * 4.63 / 29.6 = 5.47



I understand that 5.14’s are the lowest ratio that will fit in our stock front diffs, but I don’t understand how that is the perfect ratio for a 35”. I would think that one would want to stay at or lower than the stock final drive ratio.


-Rok
 

TKDx00

Lockers Installed
Founding Member
So realistically if you had 35's and wanted to get back to "stock" ratio, you would have to replace the diff(s). With what??? Where/how do I look up what will fit the X and will hold the required gears for the Diff(s)?

I think it would be helpful to have "ALL" the information in order to make a decision. Helps a person decide if they really want to start down a path that they might potentially end up stuck. IMHO.
 
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TheFauxFox

Titan Swapped / SAS'd
Founding Member
Location
Huntsville, AL
Theoretical mathematics don't always work for practical application. While your ratio is correct, it's about how the driver wants the engine to respond.

For example, several members have 33's and 4.6 gears. They end up revving a little higher to achieve the same speed, but the difference is reasonably small, which is why most people don't see the cost effectiveness of regearing. In the same way, you could get away with 5.13/4's running 37's. It's common for SASed Xterra rigs to run 5.13/4 for this reason.

There are a slew of counterproductive consequences that go with larger tires and gears, but that boils down to opinion on the durability of your rig made by the owner.

So realistically if you had 35's and wanted to get back to "stock" ratio, you would have to replace the diff(s). With what??? Where/how do I look up what will fit the X and will hold the required gears for the Diff(s)?

I think it would be helpful to have "ALL" the information in order to make a decision. Helps a person decide if they really want to start down a path that they might potentially end up stuck. IMHO.

If you wanted 35", the theoretical ratio is ~5.38 (or w/e based on rok's calc). To my knowledge, only RR and AC have gears for our 1st gens. You can't use brands such as Yukon since the gears will be splined & sized differently for D44, D60, etc...

There really isn't a go-to guide for our trucks.
 
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NMTerras

Suspension Lift
Location
New Mexico
Well, as it turns out, and to my surprise, I in fact have 4.6 gearing and not the 4.9 I thought I did. Should have checked my sticker instead of relying on what nissan said about which trucks got which gears way back then. But anyway...this ratio with 33s (33.4 actually) is annoying on the highway. With the cold air, headers, etc., I still lose steam on hills I used to fly over in fifth. I'm contemplating switching to 5.13s or 5.14s, but am holding back because of my potential impending front axle swap.

TKD, "ALL the information" is a boatload of information indeed, and there is no comprehensive guide. With regard to Xterras, there's people out there who know what they're doing, people who think they know what they're doing, people who are trying to figure out what they're doing (that's me) and idiots (occasionally also me). Best thing you can do is educate yourself. With regard to gearing and drivetrain, especially swapping, ronin wheelers and pirate have some pretty good info, but take what you read with a grain of salt and consider the source. The trick is to figure out when you're reading something from someone who knows what they're doing. You might also want to consult the google genie with some basic search terms related to diffs and gear ratios.

Now, if you could get all the info together into one place, organized and accurate, I can almost promise you a thread sticky...

:kewl:
 

NMTerras

Suspension Lift
Location
New Mexico
Also, 5.14s and 35s will work just fine. They just won't be "perfect" as Rok said. But if you want to keep your H233b, that's what you can do. If you want to swap out your rear axle, the options are somewhat endless (and by this I mean more than I am specifically aware of), depending on your willingness to mod/fab or have someone else do it.
IMHO, out H233B's are pretty good axles, and if you're not going over 35s, and can live with a gear ratio slightly lower than original drive, you're not leaving anything out there by keeping it, especially if you're not swapping.
If you're swapping, then it all depends on what you're going to do with the front whether you can or should keep your stock rear axle.
 

TKDx00

Lockers Installed
Founding Member
Theoretical mathematics don't always work for practical application. While your ratio is correct, it's about how the driver wants the engine to respond.

For example, several members have 33's and 4.6 gears. They end up revving a little higher to achieve the same speed, but the difference is reasonably small, which is why most people don't see the cost effectiveness of regearing. In the same way, you could get away with 5.13/4's running 37's. It's common for SASed Xterra rigs to run 5.13/4 for this reason.

There are a slew of counterproductive consequences that go with larger tires and gears, but that boils down to opinion on the durability of your rig made by the owner.

If you wanted 35", the theoretical ratio is ~5.38 (or w/e based on rok's calc). To my knowledge, only RR and AC have gears for our 1st gens. You can't use brands such as Yukon since the gears will be splined & sized differently for D44, D60, etc...

There really isn't a go-to guide for our trucks.

I just sent RR an email asking this very question. Just looking for someplace to start looking. The problem I seem to have run into is that the H233B and front Diff will only fit upto 5.13/14's. If in fact something larger (Physically) is needed then is there an IFS Diff that will fit the X that will allow the larger to fit.

TKD, "ALL the information" is a boatload of information indeed, and there is no comprehensive guide. With regard to Xterras, there's people out there who know what they're doing, people who think they know what they're doing, people who are trying to figure out what they're doing (that's me) and idiots (occasionally also me). Best thing you can do is educate yourself. With regard to gearing and drivetrain, especially swapping, ronin wheelers and pirate have some pretty good info, but take what you read with a grain of salt and consider the source. The trick is to figure out when you're reading something from someone who knows what they're doing. You might also want to consult the google genie with some basic search terms related to diffs and gear ratios.
Now, if you could get all the info together into one place, organized and accurate, I can almost promise you a thread sticky
:kewl:

Believe me when I say I know about the different types of people out here in the cyberworld. I've had to learn a thing or two the hard way over the years. But by getting opinions/facts from a wide source, I can sift thru and pull out what I need to look into for verification. I take NOTHING as concrete (no offense to anyone reading this). Everything is taken with a gran of sand(I don't eat salt...lol). Who knows this all may end up a wild goose chase, but at least I will gain some knowledge that could help someone in the future BUT if all goes as intended... Steena will be as I see her in my head.

No swapping and not SASing. Call me foolish or stupid but Im determined to use what we've got to get where I want to go. Well maybe the engine and tranny if things work out...lol
 
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rokdaddy

Wheeling
Founding Member
Location
New Mexico
Theoretical mathematics don't always work for practical application. While your ratio is correct, it's about how the driver wants the engine to respond.

Sometimes that’s true but my question isn’t about theory; it’s about changing a gear ratio to compensate for a 35” tire. We know what the stock final drive ratio is, if we are re gearing for performance, why not at least re gear the same as stock. I consider “perfect” to be something lower than stock if I want to compensate for increased tire diameter AND added weight. Anything higher than the stock final drive seems to be a “the best I can do” kinda thing. Nothing wrong with that… but it’s not perfect or ideal.


For example, several members have 33's and 4.6 gears. They end up revving a little higher to achieve the same speed, but the difference is reasonably small, which is why most people don't see the cost effectiveness of regearing. In the same way, you could get away with 5.13/4's running 37's. It's common for SASed Xterra rigs to run 5.13/4 for this reason.

Not sure what you mean by 5.13/4. What does the 4 describe?

Also, gearing isn’t always about where you are in the engines power band (RPM’s). Lowering your final drive ratio anywhere along the power transmission line will increase torque, regardless of what the engine is doing.


If you wanted 35", the theoretical ratio is ~5.38 (or w/e based on rok's calc). To my knowledge, only RR and AC have gears for our 1st gens. You can't use brands such as Yukon since the gears will be splined & sized differently for D44, D60, etc... .

The theoretical target is actually 5.47. You rounded down to 5.38 which is the next common ratio down from the theoretical 5.47. We’re already way out of the range that will fit into a Gen 1 IFS diff, why not round up to a 5.57? Regardless, rounding down is not ideal, it’s simply doing the best you can with what you have available.

Unless there is some performance improvement in going with a higher ratio, 5.14:1 is almost an exact match for a 33” tire. The same gearing for a 35” tire is just a compromise.


Maybe I'm missing something here… that’s why I threw out the question.


-Rok
 
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rokdaddy

Wheeling
Founding Member
Location
New Mexico
Also, 5.14s and 35s will work just fine. They just won't be "perfect" as Rok said. But if you want to keep your H233b, that's what you can do. If you want to swap out your rear axle, the options are somewhat endless (and by this I mean more than I am specifically aware of), depending on your willingness to mod/fab or have someone else do it.
IMHO, out H233B's are pretty good axles, and if you're not going over 35s, and can live with a gear ratio slightly lower than original drive, you're not leaving anything out there by keeping it, especially if you're not swapping.
If you're swapping, then it all depends on what you're going to do with the front whether you can or should keep your stock rear axle.

Well stated Sean.
 

TKDx00

Lockers Installed
Founding Member
Do I need to get worried that my fellow XN'rs might be getting into a heated discussion over lil ol' me?!?!?!
Fellas, IDC if you think the stream is cold...cause I already know how deep it is... BWAHAHAHAHA :lols:
 

TheFauxFox

Titan Swapped / SAS'd
Founding Member
Location
Huntsville, AL
I'm not heated... hope I didn't come across that way.



-Rok

Nope. :D

I was on my iPad when I typed that and the last number I remember was 5.38. Just so we're on the same page, 5.13/4 was shorthand (again, on iPad) for saying 5.13 or 5.14 (for us), since standard gear sets are 5.13 as opposed to our 5.14. I was simply agreeing with you :D, though it may have seemed round-about.
 

ChiXterra

Wheeling
Dana 44 front is about $250-$350 in somewhat decent shape, add gears, and all the necessary parts to re-build it, and you're talking more than $500. That is just for the axle. Now add in coilovers, or some other type of spring, etc., and you're talking big money. Hence the reason I am still trying to sell some of the SAS stuff I have. But yes, 5.13's and 35" tires work out to be close to the stock ratio with stock tires.
 

rokdaddy

Wheeling
Founding Member
Location
New Mexico
Dana 44 front is about $250-$350 in somewhat decent shape, add gears, and all the necessary parts to re-build it, and you're talking more than $500. That is just for the axle. Now add in coilovers, or some other type of spring, etc., and you're talking big money. Hence the reason I am still trying to sell some of the SAS stuff I have. But yes, 5.13's and 35" tires work out to be close to the stock ratio with stock tires.

Very true. I'm still trying to decide if it is worth the $1500+ (not counting suspension) that it will cost to re build mine.

You say that 5.13'S are close to the ideal ratio for 35's, do you mind elaborating on that? How did you come to that conclusion?


-Rok
 

NMTerras

Suspension Lift
Location
New Mexico
^^^Not sure he said close to ideal, just close...which as we have discussed is as close as you can get and keep the stock rear axle, right?
 

rokdaddy

Wheeling
Founding Member
Location
New Mexico
^^^Not sure he said close to ideal, just close...which as we have discussed is as close as you can get and keep the stock rear axle, right?

I didn't see any mention of stock axles but it doesn't really matter; the front (IFS) axle is the limiting factor. The rear H233b will accommodate up to 5.857's. If you're swapping out the front, the sky's the limit for the H233b.

That's why the 5.57's (mentioned earlier) were so appealing. It may be difficult to find a good match for the front axle but if it's possible, that is the ratio that will get you closest to the stock final drive. https://ruggedrocksoffroad.com/niss...p-6011.html?osCsid=5phlejmi2gpqu86400ipkqfpa7



-Rok
 
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NMTerras

Suspension Lift
Location
New Mexico
I am in a tremendous pre-moab pickle...ordered the rear ARB locker, but since I don't know whether I'm going to get the swap done before MOAB I'm considering just slamming it in there with the stock 4.6 gears, knowing that when the swap happens, and i switch to 35s, I'm going to have to re-gear. But, since I'm putting the crawler t-case in at Moab, I should be able to live with the stock gears for the time being. It just bugs me to go into the pumpkin twice...
 

rokdaddy

Wheeling
Founding Member
Location
New Mexico
^^^ Re-gearing isn't that big of a deal (weekend job) and the H233b rear is a lot easier to adjust than the front IFS diff. I'd just slap that baby in and worry about the re-gear later.
 

ChiXterra

Wheeling
Very true. I'm still trying to decide if it is worth the $1500+ (not counting suspension) that it will cost to re build mine.

You say that 5.13'S are close to the ideal ratio for 35's, do you mind elaborating on that? How did you come to that conclusion?


-Rok

This info was given to me by Cyclemut, who has done a few SAS conversions. I think it's worth it, but money got tight, and I needed to put money elsewhere.


Sent from my iPhone
 

ChiXterra

Wheeling
What SAS stuff do you have?

Brand new Calmini shock hoops (SAS hoops powdercoated black) with bumpstops, 5.13 gears for a 1978/1979 Bronco/F-150 D44 Front, Ruff Stuff rear perches, shock tabs, u bolts and hardware for a Ford 9" tube, and some other crap taking up my workbench.


Sent from my iPhone
 

UofA_Xterra

Bought an X
Location
NV
I have too questions that I hope don't sound stupid, but I've just started my research for gearing and lockers.

As the numerical number of the differential gear goes up the pinion size decreases... correct? So when upgrading to 5.14 gearing is there any significant increased in potential for breakage, compared to the 4.9 stock gears?

I think I plan to top out with 33 X 12.5 R15 tires, will stay IFS, and I have AC T-case gears. Will my 4-low gearing be too low with the 5.14 gears?

Thanks for the info!
 

rokdaddy

Wheeling
Founding Member
Location
New Mexico
I'm no expert either but it does sound like you have a decent grasp of the subject. Your question is far from stupid.

You're correct, as the ratio number increases, pinion size decreases. I'm glad that you mentioned this as it is about the only downside to gearing too low. I was kinda hoping that someone would say that they think that 5.14's are the best choice for 35" tires because of pinion size or front axle gear choices. Either of these would be good reasons to not go past 5.14 but no one has spoken up yet.

To answer your question using the limited knowledge that I have regarding hypoid diff gears:

One of the design rules of thumb for hypoid gears is to maintain between two and three gear meshes between the ring and pinion. The Nismo 5.14 sets are on the conservative end of this rule; the front (IFS) set has three meshes (barely) and the rear almost has four. I couldn't get close up shots that were good enough to show the meshes but here are shots of the sets:

Rear (H233b) gear set:
IMG_0261_zps2d8dd477.jpg

IMG_0260_zpsccc0e4e8.jpg


Front (IFS) gear set:
IMG_0263_zps93ca15d6.jpg

IMG_0262_zpsf253a694.jpg



I looks like we could go lower and still have a solid two tooth mesh. C'mon... there must be at least a few hardcore gearheads reading this, what do you guys think?


-Rok
 
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Edodrian

Lockers Installed
Supporting Member
Location
Nitro, WV
Im still a toss up between 5.13 5.14 gears or going to the far end of the spectrum and going toward the 5.857 rears, which are as close to the 5.89s available for the dana 44. Its still in the 1% ive been told so I am guessing its safe to do.
I've been told that the front axle pulls more than the rear. Anyone out there that can confirm this?

Sent from my GT-N8013
 
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