diffy concerns

OK, I'm getting a little antsy about my new X. If what I'm reading on this and other forums is true, I've purchased the worst X possible in terms of diffy problems, i.e., an '07 Off Road w/ manual trans. What gives? What's the consensus here? Are there any steps I can take to maximize diffy life, such as switching to synthetic fluids, etc? Should I avoid certain types of driving (please don't say off road!)? Or is it just crap and should I start saving for an after market upgrade for the inevitable day when it bombs? ...JB

Have fun but don't do any mods that aren't easily removed in case you need a warranty claim. I.e. 5" Lift, bigger tires, etc.

'06 and up X's seem to have less issues with the Rear Diff, but it takes a while before people get sufficient mileage to have a breakdown.

My rear went at about 24K Miles, but didn't blow until the Dealer test drove it. All Warranty.

I think you should follow that advice, no mods, use the stock tire size and get an extended warranty. I have a 05' with 20k on it now and used it for light off-road and snow driving. No issues yet but I'm going to get a 7 year 100k warranty just in case. I think that your not seeing everyone having the problem, it seems like the guys doing the really hard off-roading with big tires are having most of the problems.

If this keeps us Nissan is going to have a very expensive recall.

I bought the 7/100 extended warranty w/ the X, so I'm good there. Really extreme off roading isn't in my future as far as I know, and if it ever is, maybe I'll just mod the crap out of it (literally) and replace the crap w/ stuff that works. Thanks for your replies............JB

It doesn't take much to have a problem though... in June we busted an axle and blew out our front diff driving through some ruts at Hungry Valley... our X was only 4 months old and had less than 10k on it... Nissan's first question was did we hit a rock(abuse)but after seeing our full set of Shrock skids they covered it and the X was up and running in 4 days... oddly enough, 2 weeks ago we popped a front swaybar link about 10 feet from the spot where we blew the diff (The Nissan Black Hole of Hungry Valley) and after asking the rock question again Nissan fixed that too...

a word of warning, unless your long term warranty covers any damage it will probably still be subject to the "abuse" defence that a lot of dealers immediately raise...

Interesting. I thought I was the only one that had thoughts about issues with the diff's. I do get a howl out of the rear on my 06 on the highway around 70mph, but only when maintaining speed. And this is a vehicle that primarily sees highway driving, only occasional off road use.

Make sure you tell your Service advisor the next time you take it in for an oil change, etc. Documentation is your friend.

I'm concerned!!! I had a VW Torureg and got rid of it because I did not want to stuck somewhere.

Thought the X would be a lot more reliable, but now somewhat worried about the diff. Had a 88 Pathfinder and never had a problem with it @315k and the guy I sold it to now has 366k and still no problems,(other than one new transmission and 2 timing belts).
Wish I could still have the good feeling about reliability as I did with the Pathfinder.

Having been someone who went through both a front and rear diff.

Keep the wheel spin down. Keep off the skinny pedal. and cross your fingers.

The front diff went on a muddy hill climb, but I didn't think I had much wheel spin at all.

The rear, I'll be honest, no idea what happened. 2 weeks after the last time I wheeled, I was doing 15-20mph down a residential street, made a turn onto a street and POP.

I'm going to still wheel the X, but I think the Jeep will be the one that gets beat up from now on.

I wouldn't worry too much, but don't do anything to make the Dealer question your warranty claim.

The '05 OR's seem to have the most issues with the rear and the 2 spider gear setup, but they replace with a 4 gear setup and so far I haven't had any problems.

Time will tell and I'll let everyone know what happens if it does.

Saw the extended Jeep with a bunch of friends this past weekend 4x4ing. Liked it, probably will be my next truck. Also, we have a Nissan "headquarters" along the freeway in Huntington Beach area, plan on going there and seeing if someone will speak to me about the diff problem.

Eh, the 4dr Jeeps are not all they are cracked up to be.

I know of 3 that have caught fire for no good reason

They are under powered (who ever thought putting a minivan engine in a Jeep was a good idea needs to be fired).

They are a Jeep...they will break.

One of my friends tried pushing me into a jeep, his brother sells them. Thought it was kinda strange that the grand cherokee comes stock with a class 2 hitch. Said no way, went with the X instead and love it.

It does go in next week for an oil change and they are going to look at the rear at the same time. Service manager said the howl is not normal, if they can get it to do it they will open it up and look.

Well, according to Nissan, there is no problem.. It's all operator abuse in their eyes, but good luck anyhow.

I'll take your advice and go light on the mods. I don't think I'm going to need too many for my intended use, anyhow. I'm thinking definitely sliders, probably Shrock. The lift issue is still up in the air; just really don't think I need that, and it would be a pain to "normalize" the truck if I had to take it in for a busted diffy under warranty. the idea of some day getting a nice strong front (and possibly rear) bumper to replace the plastic fiasco on there now, and that would probably require some sort of lift to compensate for the weight sag. could I just punch up the springs to handle this?
Thanks..........beddie bye time ....JB

Just dont take it off-road and you will be ok. It only took a few trips to blow my rear and it has been sitting for 5 months at the dealer while I pursure a lawsuit against Nissan. They are agressively trying to crawl away from there diff design flaws, as they think they will save a few 100 million that way. Nissan has 0 commitment to the off-road community it appears and while reliability is greatly up over early Xterras, the exploding diffs, troublesome electric t/case and other issues make this truck not look like a trail or expedition rig, just a soccer mom mobile with an off-road sticker. Myself I am wheeling my 250K beat to hell Montero on stock diffs and 35s for another 2 years until I pay the X off and the J/K gets a better engine. Even now, atleast if the J/K stauled or burned they would fix it, Nissan says I should not have installed a lift they premote and designed or ever gone off-road...

Exactly what happens when the diff goes? Are there noises for a while first? Does it go all of a sudden? Can the truck still be driven a little, or is it totally dead? Also, if it goes go and then Nissan fixes it, is it OK and better than stock?
And...heard the 05's are more prone, true? Thanks

Personally I had no inclination of failure, until that is, I drained the gear oil to reseal the cover and put on a shrock diff cover. I found two huge chunks of metal and knew it was going bad. Next day made an appointment and they replaced the Rear end assembly without question.

As to the better replacement, I was told by someone I have great confidence in, that the new rear-end is the '06 and up design which has 4 spider gears instead of two. There is no telling how many '05's will have issues, time will be the judgement of this.

Web Album of close up pictures of the chunks.

Thanks for the pictures. Went and checked out the Toyota FJ and the Jeep extended wheelbase unit, and did not like either one. So...I really want to keep the X. Seems that if I have the diff(s) replaced with the newer 4 spline units it would be OK. Does this seem logical??? Or...are there after market diffs out there that could be used to replace the bad diffs??? Thanks for opinions.

You're welcome and as far as I know there is not a replacement Diff unless you go drastic and so you won't have any warranty.

As far as longevity, like I said time will tell, I won't be changing my driving style and always try to keep wheel spin to nil.

You're just going to have to decide for yourself.

So I'm sure this issue is getting old but here's my one question... Are '06-07's o.k.? I was thinking about an automatic 06 or 07 "S" model. I had an '05 six speed that had the worst clutch ever but no diff. problems. Well my fiance totaled it last weekend and I want another X but not if there's not a quality year to buy. I can't wait for the 08's, must buy now. Someone with some know, tell me what you would buy if you needed a reliable rig that was to be used 75% highway and 25% off-road. (nothing too extreme mainly mud, snow and trails on the way to camping spots)Usually pulling two atv's. Thanks.

Ok, so what would it take to throw some aftermarket diffs in the front and rear?

13-18K would do it. There will be cheaper solutions coming out, probably 5-6K some day.

I have been reading the thread on the differentials and it appears that with the 4 spider gears in the 06 the problem has been resolved for the rear dif, but the jury is out on the front dif problems. I also saw a response from Xterraracer that he was working on a solution also.

I think the offroading you describe would be fine...my bud with an '06 OR has had zero problems for example, and he does Rousch, etc as well.

It SEEMS to be more of an '05 issue, and maybe later year's that used the 2 gear rear instead of the 4 gear version.

Certainly the newer 4 spider rears will be better, but the factory locking versions still have a thin cut side gear. And the front is just hopeless all years.

I have an appointment for tuesday to take my 06 OR in and have the rear differential checked. For the last 3 weeks I have had a vibration from 25 to 35 mph. This friday I had my tires rotated and rebalanced in case that was the problem. After driving it they put it in the air and put it in gear. There was a grinding sound coming from the rear differential when they held one of the rear wheels. I have not really had my X off road. I have had it on dirt roads in 4 wheel drive 3 times. I have been towing a travel trailer with a dry weight of 2840 a couple of time for a total of 500 miles. This does not sound good.

Keep us updated.....

Is it true you really have your X parked until the diff situation is solved? I plan on going to the dealer to find out if the diffs are covered past the 36k warranty under the 60k powertrain warranty. Do you happen to know? Thanks

Stay off the skinny pedal! Don't spin your tires like an idiot when they come loose. Don't hang tires that are a couple of inches bigger and twenty or more pounds heavier. Don't drive around for ten - twenty miles with the rear differential locked.

I parked it until now. Next week it goes to a mechanic and to try and see if the Titan Trac Loc will replace the stock POS locker, while the lawsuit begins.

But yes, the differential should be covered under the 60K power train.

As far as staying off the skinny pedal? I did. As far as bigger tires, 1"? Talk about delicate.

Just a side note, the complaint Nissan had about a larger tire, was that it with the lift raised the vehicle, which created leverage against the differential They gave that one up before the extra torque from the lifted pinon angle

In the case of my Xterra, It still has the stock tires. At 12,000 miles I cannot justify replacing them. When the time comes, though, I planned on replacing them with the BFG 32" tires. I have also pretty much kept off the gas since I hate what that does to the gas mileage.

Please let us know about the Titan Trac Loc exchange. Will it still be a differential lock or just a locking differential?? I don't mind spending money to replace the diffs since there is no other vehicle that I want. Thanks Also, a great site about 4x4 and diffs is http://www.4x4abc.com/ML320/ml320_traction_etc.html

It will be just a LSD.

a larger tire size def would create more "leverage" against the diff.

Against the SPIDER GEARS though?

whatever tangential force is applied to the cirsumference of the tire will be transferred as torque along the shaft and into the diff, gears transfer that force along on the gear train. whatever the weakest point in the train is what ends up fatiguing or blowing first. the larger the tire, the larger the moment that is initially created causing more force to be sent down the line to further components.

Of course MANY people have broken with stock tires. Would be interesting to know how much another 1" of tire really would add....Any automotive engineers out there?

I still will rehash.....A Rubicon 44 handles 35-37" tires, a stock 20 year old Montero that came with a P225 handles 35-37" tires, THEN you start with an occasional axle break. So whatever the forces on the Nissan D44, clearly it was under engineered.

I agree, there is no way you can point to 1" larger over factory as the problem. Sure it's might be a cause, but it's not the problem. I could see this argument if the stock tires were 28's and you were putting 33's on, but that's not the case. The stock tires on an OR model are 32x10.50x16 and more people are running 33x11.50x16. We are not talking about a large jump in size here.

Now, what i will say is the weight difference between the stock tires and most of the more aggressive off-road tire is quite a bit (even staying with the same size). But again, I point to the fact that with with the D35 in Jeep (which are just axles), people break axle shafts a lot sooner than they blow up diffs.

Having your diff the weakest part of the driveline is the stupidest thing I ever heard. I would not be afraid or complain one bit if I was blowing half shafts or axle shafts. That can be expected.

nissan could have made the diffs stronger, but they didn't. It sucks, but they could "prove" that larger tires caused the failure because theoretically they can. even though it prob isnt why it failed in reality. those diffs prob would have failed regardless. larger tires could cause it to fail sooner though based on the fact that it causes overall higher alternating stresses thus shortening its overall lifespan.

Mikey I understand your principle, and I have applied it to a failure on my 1990 Montero. Designed for 225 tires, and having 33s then 35s for the last 100,000 miles. Both rear axles incurred a slight twist in the splines causing rear axle leaks. This is a well documented fatigue failure on 4x4s with large tires. Luckilly it took a long time to happen.

But fatigue failure on spider gears? And after only 6 trips off-road, 5 of which short, casual trips? And only 2 trips with a 1" larger tire?

I submit they CANNOT prove that the larger tire or lift alone could have caused the failure. AND...
They have to argue why...

1. There are thousands of failures of the exact same nature, regardless of use off-road or tire size.
2. Why they switched to a 4 spider diff sometime in 06.
3. Prove that the 2 spider gears, small cross pin and thin locker gear are not under engineered.
4. Why they promoted and helped design the lift, and display it on no less then 2 company vehicles and allow dealers to install them.
5. Why there diffs are some of the only ones ever designed with such a small factor that they cannot handle stock tires or 1" larger tires, including the brutally weak D35. And why are they 40% smaller/ weaker then prior Xterras with smaller tires, less HP and Torque and less weight? And why can everyone run 33s on those diffs without explosions?

I believe the new Rubicon axles are essentially the same thing the Nissans have. The difference - a lighter truck and less HP, but I wouldn't be surprised that as we see lifts, etc. going on the new 2007+ Rubi's, they'll be having failures too.

Add 80+ HP over the old models and put in much weaker axles. I just don't understand the thought process.

Nissan better address this. Myself, I'd love a new Frontier, but this will keep me from buying one, unless I get one with the full intent of doing a SAS and swapping out both axles.

If that's the case Andy, You definately wouldn't be buying it off a Dealer lot and having next to Zero mileage.

I'm sure you can find someone at some point that may have no warranty and a blown diff and pick it up that much cheaper. Sucks for them, good for you.

this may be a crazy question, but does anyone know if CAD files are easily obtained for the D44 spider gears? I could just throw one onto one of my company templates, spec out a better steel, and have our machine shop quote a price.

The Rubicon may have the same axles, but not the same differential carrier and weak components, that is a Nissan special. The problem is not just weak spiders. It is 2 Vs 4 needed in early models, and the shaved side gear for the locker. To fix the problem the locker would need re-designed I think.

The only side gear I can recall breaking was being used in an off-road Race truck.

I don't remember reading about any other side gear issues, just Spider gears.

Mikeyo you just call up Dana and ask them for the CAD I'm sure they'll comply.

I hope that someday, if the 4 gear setup is proven unreliable, someone will machine new spider gears to use. I know Xterraracer is working on a Spool, but that would suck on a daily driver.

Other than that save up on the Mod money for Sas and better 3rd member. Definately keep the X unmodified until then to keep the warranty intact.

I honestly don't think anyone knows that has been failing in the rear. My dealer didn't open it up and wouldn't let me. They said it had to go back to Nissan like it was.

So it could have been a side gear.

The Tech Inspector checked it out and listed cross pin and spiders, as to be expected. Mine is being towed to a shop now. Will check it out myself.

The side gear is certainly more of an unknown. But if I read Xterra Racers tone of voice from his typing...its gonna be a problem, especially with bigger tires. Remember, it really takes 35s to hang out on trails today. 32s blow the spiders...35s....

I wouldn't rule it out as problematic, but until we see some everyday use causing it issues I'll disregard it as isolated.

32's are Stock, 35's yeah would be nice, but impractible for most people and the lift required to stuff them is pricey at best. SAS would be the correct route regardless if you wanted to "hang on the trails".

Good luck at the shop and I hope you can post a couple pictures of your diff.

My dealer called me tuesday night to advise me that they were ordering the parts to replace the rear differential for my 2006 OR. As I have stated above I have not really taken my vehicle off road. I have used 4 wheel drive several about 4 times on pretty poor dirt roads. The one thing I have done out of the ordinary is that I tow a camp trailer. The dry weight is 3840 lbs so it is well below the tow capacity of my X.

Has anyone been able to pin-point when in 06' that the 4 spider pkg was being installed? Mine is a Feb. truck. Anyone know?

Went to a dealer that had 3 07 OR's on the lot and 1 used 06 OR. Checked the diff covers. Mine, a 05 OR and the 06 OR on the lot had no inprinted numbers or letters on the covers. All 3 07's had numbers with 36-06 large and easy to see. So... I would conclude that the new and OK diffs are easy to spot.

And...talked to the service manager, said only one X has come in with diff problems, numerous Titans have been in with problems, interesting. (Mossy-Oceanside)

Just FYI...

1990 Montero
Base Number of Cylinders: 6 Base Engine Size: 3 liters
Base Engine Type: V6 Horsepower: 143 hp
Max Horsepower: 5000 rpm Torque: 168 ft-lbs.
Curb Weight: 3494 lbs.

2005 Xterra
Base Number of Cylinders: 6 Base Engine Size: 4 liters
Base Engine Type: V6 Horsepower: 265 hp
Max Horsepower: 5600 rpm Torque: 284 ft-lbs.
Curb Weight: 4375 lbs.

The only thing that explains is why the Montero isn't snapping axle shafts.

I saw some comparisons else where, in regards to Toyota. The fact is the 3.0 V6 rear exceeds specs for a Ford 9", the front a Toyota 8.5". This is all components, axles, ring gear, ect. The newer 3.5V6 200-245HP trucks use a 10" rear end, around a dana 60 spec. So you have to ask, why did Nissan use smaller diffs with more power, yet fairly beefy axles? It makes no sense, other then costs. That was somewhat the conclusion on the Toyota discussion. Still, cost savings do no good if you are left holding the bag for millions of dollars in warranty work, and pissed of customers. And, they took the cost to build and engineer a solid engine and transmission.

The information below is interesting but not very useful since the problem does not seem to be ring gear size but spider gear or side gear weakness.

New Tundra differentials:

The V6 and 4.7 liter V8 get the differential with a 9 1/2 inch ring gear. This gear comes in two ratios depending on whether or not you order the towing package. This is the largest ring gear of any 1/2 ton full-size pickup truck. The 5.7 liter engine comes with an even larger 10.5 inch gear which is larger than most 3/4 ton pickup trucks.

FJ differentials:

An electronic locking rear differential with an eight-inch ring gear is available. The ring gear in the front differential of the 4x4 FJ Cruiser also measures eight inches.

Dana 44's - Nissan 8.5 inch

I still maintane its not the overall diff size that is our problem. It is just bad, cheap engineering. The stupid 2 spider trick, crappy front diff housing and thin cut locker gear. ALL of that could have been avoided for a couple of average strength diffs, instead of brittle like glass.

The Montero diffs are definately over engineered I will give you.

I had the same exact problem. Thought that was just "what they all did". Finally took it in at around 23K and asked about it. They told me the diff was bad, and they replaced the entire rear end. After that the ride was MUCH quieter...something was def wrong with the original.

BUT, I've had a hell of a time with the dealership because they continue to screw things up. It's been back to the shop 4 times since I got it "fixed". First, the rear seal started leaking. Took it back and they replaced the seal. The next day I heard a grinding noise from underneath, so I crawled under and found that the sleeve around the yoke (on the driveshaft) was grinding on the extended part of the transmission. Took it back and they told me the drive shaft was "coming apart". They replaced the driveshaft and the extension case, and everything seemed good. I clawled under the X the next day to check out the work and found that the driveshaft was new, but the sleeve (that was causing the grinding) was missing, leaving my rear seal exposed and making me wonder if there is an alignment issue. Took it back and pretty much went off on the service writer. He talked the the mechanic and they claim that it came from Nissan like that but they have ordered a new one that "will include the sleeve". Now I'm just waiting for the part to come in...

BTW, It doesn't look like they have aligned the wheels after the diff replacement, at least it's not in the paperwork. Wouldn't that be a requirement? Seems like common sense to me... Should I press them on that?

Dealership I use is pretty good. I refuse to use the one down the road from me, even though it would save me an hour of driving for service, they are idiots and couldn't diagnose a flat tire correctly. I go in on Tuesday, they are going to check out the rear diff along with the passenger window rattle (regulator according to the service manager) so when I get it back everything should be done correctly. I hope.

Got my 06 off road back friday. Cost for replacing the rear differential was $2500.00. Glad this was under warranty. I haven't crawled under my X to see if I now have a differential with numbers on it. I really like my X, but if this is going to continue to be a problem I am going to have to consider getting rid of it.

There's no alignment to be done on a solid axle rear. The springs locate the axle, and the center pins in the spring packs line up under holes in the axle spring perches.