Maybe this is where I need to ask. What about gearing changes when you put larger tires on the X? I know if you don't change the gears you get less power transferred to the ground. Are any of you with larger tires making the change? If not what sort of fuel inefficiencies are you noticing? What about power losses? Surely you aren't complaining about LSDs if you change tire sizes without changing gearing! I posted on 4 something no replys.......... Is it just boring?

I don't think anyone has taken the jump yet to switching gears? I would like to do lockers and Transfer case gears. I run stock tires during the week so that is the reason I won't switch to taller gears in the front a rear. I do have a power loss with the 31" Swampers but it's a liveable loss

Originally posted by Aythya
Maybe this is where I need to ask. What about gearing changes when you put larger tires on the X? I know if you don't change the gears you get less power transferred to the ground. Are any of you with larger tires making the change? If not what sort of fuel inefficiencies are you noticing? What about power losses? Surely you aren't complaining about LSDs if you change tire sizes without changing gearing! I posted on 4 something no replys.......... Is it just boring?

Actually it has been discussed many times. Here are my thoughts regarding R&P gears. Unless you own an SC X, changing the R&P is not going to be the best solution to power loss from tire changes. The Xterra uses a 4.63/1 R&P. This is one stout R&P ratio! The problem with changing gears to compensate for larger tires is that at that ratio, you are merely restoring factory power. The Xterras biggest problem is the lack of hp. If you increase the hp, the 4.63 R&P is an excellent gear set. As time goes by, more and more stuff is being offered for the X. As that occurs, you are better off spending the money you would have spent on gears (and believe me when I say that is outrageously expensive on an X) on engine modifications to increase hp.

Originally posted by warmonger


The problem with changing gears to compensate for larger tires is that at that ratio, you are merely restoring factory power.

That's not a problem, that's the reason for doing it. R & P sets from SLR are $475 a set. Agreed, that is expensive. Gears for a Dana 44 are about $150. However, I'm not sure what you could do to the engine that would be any cheaper.

Personally, I would prefer to leave my engine stock and reliable. Alot of Toyota guys run super low gears and the stock 22R 4 cylinder engine. To me, that seems like the best direction to follow in building up an Xterra.

AC offers RP sets as well.

As for me, my 31's are fine with the stock gears. 32's would be OK if you aren't towing a trailer. I would definitely consider regearing with 33's though.

Optionally, you could get 4:1 t-case gears from Calmini if you are only concerned with gearing offroad and not on.

Nissan RP gears are low in comparison to those put in other manufacturers, but the transmission gears are taller. The final drive ratio/crawl ratio on Xterra's actually turn out to be about the same as other manufactures final drive/crawl ratios.

Originally posted by wqbang

Nissan RP gears are low in comparison to those put in other manufacturers, but the transmission gears are taller. The final drive ratio/crawl ratio on Xterra's actually turn out to be about the same as other manufactures final drive/crawl ratios.

I have been wondering about the transmission gearing. In one of the Four Wheeler of the year competitions I read a while back, the Frontier actually finished near the bottom in their crawl test. They just put all the trucks in first gear and idled toward the finish line, and the last one to the finish line was the winner. It is kind of an unscientific test. However, I thought it was strange that the Frontier would do poorly with the low ring and pinion gearing we all have. I know our transfer case gearing is tall. I agree that transfer case gears would probably be a better choice than R & P gears, unless your highway performance is poor. Also, I think I read that the transfer case gear installation is a do it yourself job.

Thanks to all!! Now that's the kind of info and discussion I'm used to seeing here.

I am not all that familiar with the Frontier RP offerings. I know that the Crawl ratio with the Auto Tranny less than that of the 5speed for obvious reasons. Also, Xterra's without LSD's were equiped with taller RP than those with LSD's.

Considering I saw an Xterra on the trail this weekend turning skinny 36" Swampers (yes, 36) with a stock driveline on some pretty nasty conditions, I think we're in decent shape already.
I also saw a 3.0L Hardbody turning skinny 38" Swampers very effectively with the stock driveline as well.

Pictures to follow in the next day or so,
Brent

36's? Is this a joke i.e. the TwinTurbo thread over on XOC?

No joke. Goliath hinted about it here (http://www.automotiveforums.com/vbulletin/t43826-2.html) on Thursday...

I'll dig up a pic shortly...

Brent

Lower T-case gears make the world of a difference off-road, but unfortunately do little for on-road performance. The main point I was making is that the factory highway power in the normally aspirated X is weak to begin with. Its 0 - 60 time is not all that great even with the factory 265/70R-15 Long Trails (or whatever it is you may have). If you are satisfied with that and regaining that lost performance is important to you then go with the lower R&P. The gears will cost you $1,000 bucks plus installation of between $200 and $400 per gear set, depending on whether you remove the diffs or not. If you are doing primarily crawling and not pulling trailers up mountains, odds are you will have few issues other than passing. But if that is all you do primarily, say the heck with the R&P and get the T-case gears. You will get far more value for your money in my opinion. You can live with the slightly reduced power as long as you aren't running 35s or something.

Thanks War...

I primarily pull a trailer (boat) and no I'm not satisfied with the highway performance of the X. Especially when headed up hill in Jefferson county NC. However I would like to put 31s on my truck and not lose the performance I have now. I do drive mostly on the highway and 31s aren't a necessary just a luxury:I do hunt and fish and have some things to cross

Thanks again!;)

Nissan puts the equivalent of 31s (265/70R16 = 30.6") on the '02 SE Xterras already with the same gearing. I really don't think you'll lose any noticeable power going to 31s. You're running 265/70R15 (29.6") which were the stock size on the '00 models right? A lousy 1/2" larger radius isn't going to sap that much power. Certainly not enough to justify re-gearing.

Brent