2001 PF : Help !! Transfer Case - Can't get the plug out to check the oil level

[Almatti]

Can't get the plug out to check the oil level. Dealer & mechanic says that's a problem - probably a "frozen" situation. I now have a severe vibration at speeds over 45+. How do You Know that The Transfer Case and the internal gears are bad or warped???

[Fisherdude]

I can't get my bolt out either even with a 4 foot breaker bar. check your breaks, roters could be warped and callipers be draggin'

[Almatti]

Fisherdude: No its not the brakes. Think its narrowed down to bad "U" joint(s) and/or drive shaft..

[K03sport]

Is your vibration is 2H, 4H or both? How would a fluid change help unless you think you're losing fluid out of your xfer case?

Would it just be easier to drop the case, change the U-joints, and work on the case outside the truck?

You're positive it isn't wheel/tire related or anything at the corners...

[Almatti]

Ko3: No leak from the TC. Positive it's not wheel balancing. Had them rotated. I have new tires put on 7 weeks ago, they were fine, no belt separations. I described these issue on another thread: Transmission - Vibrations. This vibration, its really a vibration NOT a shimmy [that would be the wheels out of balance], occurs at highway - starts at 45mph, increases with throttle to about 65 mph, smooths out a bit at 70 mph (but still there), then when decelerating you feel it increase again at 55 to 45 mph, soon as you drop to 40mph, its smooth as pie. WTF. Happens worse in AUTO mode, less in 2 WD mode.... My son, who mostly drives the PF swears he didn't fall of a cliff, or take it Off road LOL.....I didn't either. This just started last week. I'm going to take it to another Nissan Dealer this week, tell them there's a virbration which is NT wheel balancing related, and let them analyze. Although, like my B-I-Law, told me, they love to give a list of things to spend my $$$$ on.

[W O T]

Does it happen in both 2wd and 4wd though? If it does, my guess would be driveshaft, I dont see why it would balance back out @ 70mph though.....

[keelhaul]

I would guess bad u joints or maybe a bad cv joint. I have a bad cv axle and I can definitely feel a vibration when in 4x4, less in 2wd, and no vibration with my hubs unlocked

[Chuck Tribolet]

Ko3: No leak from the TC. Positive it's not wheel balancing. Had them rotated. I have new tires put on 7 weeks ago, they were fine, no belt separations. I described these issue on another thread: Transmission - Vibrations. This vibration, its really a vibration NOT a shimmy [that would be the wheels out of balance], occurs at highway - starts at 45mph, increases with throttle to about 65 mph, smooths out a bit at 70 mph (but still there), then when decelerating you feel it increase again at 55 to 45 mph, soon as you drop to 40mph, its smooth as pie. WTF. Happens worse in AUTO mode, less in 2 WD mode.... My son, who mostly drives the PF swears he didn't fall of a cliff, or take it Off road LOL.....I didn't either. This just started last week. I'm going to take it to another Nissan Dealer this week, tell them there's a virbration which is NT wheel balancing related, and let them analyze. Although, like my B-I-Law, told me, they love to give a list of things to spend my $$$$ on.

Sounds like you have part-time 4WD. Looking at the schematic in the FSM,I can't see anything that would make the transfer case have a vibrationin 2WD.

Any chance you threw a wheel weight?

[Almatti]

I appreciate all this advise. man, this is a Bummer. The wheel weights are there, after I rotated the new tires last week, there is aslight "shimmy' but not causing the vibration. Took 'er to another mechanic today. His first opinion was that it is bad U joints. After they got under the PF, shook the drive shaft as many have receommended, there is a small play. but they tell me that a noise is present in the TC.... I'm to bring it back on Wednesday, to re-examine and possibly install 2 new U joints to isolate. If that doesn't do it, I'm printing out the advise here: Maybe it's CV Joint(s). Question to all: How could this vibration just suddenly appear?? is my son not telling me something? The mechanic today did say there is no sign of damage > hit something or ran into something....Can CV joints be IT. One thing: it did snow pretty heavily here in NY Suburbia on Monday, and then he told me about the appearance of this vibration on Thursday, a few days later....I will tell you folks, THIS IS "DRIVING" Me Crazy

[K03sport]

How could this vibration just suddenly appear?? is my son not telling me something?

I hope you can get it narrowed down and fixed. As far as you not thinking your son is telling you everything, there are nanny devices out there that plug into the the OBD-II port and record what the ECM is seeing - throttle %, speed, distance travled, etc - so concerned parents can monitor their child's driving habits. I also know there are super nanny devices that let you monitor their driving habits in real time online so you know exactly how they are driving within a minute or two.

I'm not saying your son is shady, but in case you want to know more about how the PF is being treated when you aren't driving, there are ways. Plus, if the kids know they are being "watched", it might make them think twice about full throttle stop light launches, etc.

Also, I think Progressive has a "pay as you drive" program with a similar device and based on how one drives will dictace how much insuarance you pay. I'm not advertizing for Progressive, I just saw this on Motorweek (PBS) with John Davis a week or so ago. I thought it was kind of interesting.

[Almatti]

chuck: It was finally determined by a great, patient new mechanic here in Westchester County, NY to be bad U joints in both driveshafts. he reomved the front shaft and showed me the one bad U joint. Thank God its not the Transfer case, although he can't check the oil b/c the pug is "frozen" [probably over torqued or not installed properly when i chnaged the diff and x-fer case oils 40k miles ago). The virbration at 45+mph is much much better, although at first start from a stop. he and i sense a slight vibration which is probably from a bad U joint on the rear shaft. He says getting the plug out (the x-fer case is NOT leaking) is going to be a problem: It's Aluminum and so is the x-fer case !!. I saw somewhere else, that a new plug hole can be drilled into the case ......I don't know about that

[Chuck Tribolet]

Aluminum on Aluminum is generally a REALLY bad idea. It galls. Basically ,the two parts weld together.

Stainless steel will do the same thing, but you have to do something dumblike using power tools to drive an SS bolt into a nut.

[K03sport]

Almatti, have you tried PB Blaster? Spray it, let it soack it, spray it, soak, etc.,...maybe over a two or three day span. Then, try and see if it will move.

The only other option I can think of is to drill out the plug. I'm guessing there isn't a lot of room under there, so pulling the TC out may be the only option.

As far as drilling a new hole and tapping it, I think it would be possible. Just put grease on the drill bit to catch the shavings and keep them out of the TC. Then, do the same thing with the tap. Cover it in grease to catch any shavings or filings. If it works on Truck-U, it can work for you too.

Will heating up the TC and plug work like it works for other stuck metal parts. I've seen plenty of automotove fab shows use heat to "unfreeze" metal parts when they are stuck together, but I'm not sure if heat and aluminum work the same as heat and steel.

[W O T]

PB blaster is garbage, it works for simple jobs, but doesnt penetrate. WD40 is the best "shelf" penetrant, but Napa sells some god awful smelling 2 part systems that absorb in and honestly disolve everything, and as long as the threads arent already stripped out, that bolt will come loose. I had to use a 2 part system on my civics axle nut. 10+ foot bar and 3 ppl couldnt break this nut, 2 days of treating and it came off with a regular 12"

If youre sure both pieces are aluminum though, I honestly wouldnt touch it, I would simply like stated, drill and tap a new hole in the case if possible, grease "works" but some chips do still get in you just have to be slow and careful.

Ive drilled a few intake manifold that way, completely removing the tap and cleaning it off every 2ish rotations keeps it real clean aswell

[Almatti]

WOT & K03,I just learned of another product : Gibbs penetrant from mechanic in NJ who conducts a weekend radio show on auto mechanics/problems. I sent him an email about this PF problem (vibration and now a "frozen" plug to the X-fer case). He read it on the air, suggested mightly that "torching' the stuck bolt is absolutely the last very carefully applied resort. That's when he recommended using Gibbs