Hello all,
Was driving on the highway today after a week or so and noticed when i was in Auto mode and reaching 80km/h, found a vibration and almost a grinding type noise. Sped up to 120km/h and noise was still there. As soon as i turned it to 2WD mode (thank goodness no snow on the highway today) the noise and vibration went away.
A side note, last week we had a great day and I was in 2WD mode and parked my car on the driveway. In the afternoon, we had snow and I had to move my car around on the driveway and forgot to change the mode and drove in 2WD mode and had the tires spin on me a bit...could this have caused the problem?
Can anyone suggest a reason why this is happening? and maybe what i can do to reduce the grinding noise...
thank you!
Vibration / Grinding in Auto Mode
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funnyman82
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Re: Vibration / Grinding in Auto Mode
Sounds like it was stuck in 4wd mode.
The truck does not have AWD -- it is not the most technical system. On dry roads in 4wd it is not always smooth - especially turning.
So its hard to tell if you have a problem without hearing the sound. Although, as I said above if you were driving on dry pavement with no slip potential the system should have switched back in 2wd.
This was the upgraded system and the intent was for it to stay in the "Auto" mode - so that 4wd would be available if needed. Mine is always in "auto" unless I am in heavy snow and I want the 4wd to be constant
Having it slip in 2wd should not have done anything. One weakness in the system is it does not tell you when it automatically switches.
With the age and miles on some now - lots of stuff can be going on.
The truck does not have AWD -- it is not the most technical system. On dry roads in 4wd it is not always smooth - especially turning.
So its hard to tell if you have a problem without hearing the sound. Although, as I said above if you were driving on dry pavement with no slip potential the system should have switched back in 2wd.
This was the upgraded system and the intent was for it to stay in the "Auto" mode - so that 4wd would be available if needed. Mine is always in "auto" unless I am in heavy snow and I want the 4wd to be constant
Having it slip in 2wd should not have done anything. One weakness in the system is it does not tell you when it automatically switches.
With the age and miles on some now - lots of stuff can be going on.
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funnyman82
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Re: Vibration / Grinding in Auto Mode
Thank you for your reply. Is it bad to drive the truck like this? On dry road in 4WD?
Re: Vibration / Grinding in Auto Mode
Bad ? Well first off its not necessary -- I believe the manual may have an upper limit on speed - but its been a while since I read it.
If you are bouncing in and out of dry pavement and then snow or if you are driving fast in flooded roads then then the 4wd Hi gives you the benefit of knowing it is in 4wd. Often when you are just driving normally in snow you do not need the 4wd as the rear tires are giving you enough traction - and you have the benefit of the auto system to take over and give you 4wd if you need it -- like pulling in a steep driveway that may look clear enough in 2wd.
Since the truck is normally in 2wd when on "auto" -- you get no benefit from the 2wd Hi in gas milage on dry pavement as it is never going to switch to 4wd anyway. It just keeps it from going into 4wd when the car senses you need it.
So the bad of 4wd Hi. The wheels are all locked together -- all turning together. The front wheels are both turning at the same speed - when you go into a turn the wheels can not turn at the same speed since they are traveling different distances. One on the outside of a circle the other further inside the same circle. Something has to give and the give is the tires - they slip on the pavement. Now the truck is designed for this but it obviously puts a strain on everything - and will over time scuff the tires. That is why you must have the same size tires on all 4 wheels.
On an awd vehicle -- the wheels can spin at different speeds - Depending on the sophistication of the system. Some can transfer all the power of the engine to only one wheel- not that you need this very often.
In your case you need to make sure the "Auto" is not keeping the system in 4wd for some reason when it should have put it back in 2wd. Read the manual and play around with it. Good luck
If you are bouncing in and out of dry pavement and then snow or if you are driving fast in flooded roads then then the 4wd Hi gives you the benefit of knowing it is in 4wd. Often when you are just driving normally in snow you do not need the 4wd as the rear tires are giving you enough traction - and you have the benefit of the auto system to take over and give you 4wd if you need it -- like pulling in a steep driveway that may look clear enough in 2wd.
Since the truck is normally in 2wd when on "auto" -- you get no benefit from the 2wd Hi in gas milage on dry pavement as it is never going to switch to 4wd anyway. It just keeps it from going into 4wd when the car senses you need it.
So the bad of 4wd Hi. The wheels are all locked together -- all turning together. The front wheels are both turning at the same speed - when you go into a turn the wheels can not turn at the same speed since they are traveling different distances. One on the outside of a circle the other further inside the same circle. Something has to give and the give is the tires - they slip on the pavement. Now the truck is designed for this but it obviously puts a strain on everything - and will over time scuff the tires. That is why you must have the same size tires on all 4 wheels.
On an awd vehicle -- the wheels can spin at different speeds - Depending on the sophistication of the system. Some can transfer all the power of the engine to only one wheel- not that you need this very often.
In your case you need to make sure the "Auto" is not keeping the system in 4wd for some reason when it should have put it back in 2wd. Read the manual and play around with it. Good luck
Re: Vibration / Grinding in Auto Mode
Your explanation forgets about the differential between the front wheels and the rear wheels. The diff allows differential speeds of outer to inner wheels, which by physics rotate at differing RPM during turns. And the rear end of 4WD QX4 are limited to the amount of slippage as to torque.
But if no maintenance or poor maintenance re oils for that rear end are miss used, the anti slip ability could be reduced.
Rear ends rarely grind unless dry since the crown and pinion are matched and equidistant but the transfer case would let you know as the transmission does with noises. The transfer case with its signal light must be fully engaged in or out but not in between. The gear cut of the transfer case are not a constant mesh, similar to a rear gear in a manual transmission and if rotated too fast make a whining gearing noise.
These blunt cut gears are machined to mesh but not run quietly as constant meshing gears.
From your text on the noise the running together of these transfer gears may have been the problem, but at 120 Km an hour you should drain the transfer case replenish it and check the oil and grindings that come out.
But if no maintenance or poor maintenance re oils for that rear end are miss used, the anti slip ability could be reduced.
Rear ends rarely grind unless dry since the crown and pinion are matched and equidistant but the transfer case would let you know as the transmission does with noises. The transfer case with its signal light must be fully engaged in or out but not in between. The gear cut of the transfer case are not a constant mesh, similar to a rear gear in a manual transmission and if rotated too fast make a whining gearing noise.
These blunt cut gears are machined to mesh but not run quietly as constant meshing gears.
From your text on the noise the running together of these transfer gears may have been the problem, but at 120 Km an hour you should drain the transfer case replenish it and check the oil and grindings that come out.
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funnyman82
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Re: Vibration / Grinding in Auto Mode
I went to have my oil and fuel filter changed and asked them to look at the front, rear, transfer case and trans fluids checked and they said it looked ok...do you think i should do a flush and fill anyway?
Is the draining and filling of the transfer case easy to do? I would like to save some money and do this myself...
thx!
Is the draining and filling of the transfer case easy to do? I would like to save some money and do this myself...
thx!
Re: Vibration / Grinding in Auto Mode
I specifically mentioned the front wheels as the rear wheels are going to allow differences regardless of the differential installed -- although I believe all the infinities had the LSD. We are talking about the fronts and the 4wd - and why he would get a vibration in 4wd - he does not get the sounds/ vibration in 2wd.
The transfer case is a simple one and must be synchromesh (although I have never opened one) because it is controlled electronically and operates over a wide range of speeds. Mine makes no noise - and I believe it is filled with the same D matic fluid.
What you need to do is make sure the transfer case is moving between 2wd and 4wd correctly when you move the knob - and also that it is returning to 2wd from 4wd when you have in on the "Auto" setting. That will address the "why was the car in 4wd on dry pavement"
But you also have to have the components of the drive going to the front wheels checked - when you shift to 4wd one of the drive shafts may be vibrating and causing this - it could be many things -- some very simple. But you should not be getting this - and I have driven mine often above 120k (75mph) for years with no ill effects.
The differentials do have a fluid service interval on them - and not knowing how many miles on the truck or when it was last changed - can't give a comment. When you say they were checked -- did he just check the level and was he also commenting on the fluid condition when he said they were OK ? Although my experience is the differential fluid always looks bad !
I would play around with it a little bit to see if you can better determine when and where the vibrations are coming from.
The services on the differentials are not difficult .....a bit messy. They do not cost very much to have done -- USE THE CORRECT FLUIDS!!
The transfer case is a simple one and must be synchromesh (although I have never opened one) because it is controlled electronically and operates over a wide range of speeds. Mine makes no noise - and I believe it is filled with the same D matic fluid.
What you need to do is make sure the transfer case is moving between 2wd and 4wd correctly when you move the knob - and also that it is returning to 2wd from 4wd when you have in on the "Auto" setting. That will address the "why was the car in 4wd on dry pavement"
But you also have to have the components of the drive going to the front wheels checked - when you shift to 4wd one of the drive shafts may be vibrating and causing this - it could be many things -- some very simple. But you should not be getting this - and I have driven mine often above 120k (75mph) for years with no ill effects.
The differentials do have a fluid service interval on them - and not knowing how many miles on the truck or when it was last changed - can't give a comment. When you say they were checked -- did he just check the level and was he also commenting on the fluid condition when he said they were OK ? Although my experience is the differential fluid always looks bad !
I would play around with it a little bit to see if you can better determine when and where the vibrations are coming from.
The services on the differentials are not difficult .....a bit messy. They do not cost very much to have done -- USE THE CORRECT FLUIDS!!
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Innovazn
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Re: Vibration / Grinding in Auto Mode
From my understanding, While in Auto, you should not exceed 60 KM/H. can anyone add insight on this? that may have been causing your "vibrations" I have exceeded the suggested limit like you have too and have felt this vibration (promptly slowing down) and did not hear this grinding.
Re: Vibration / Grinding in Auto Mode
"Auto" is the normal setting -- you can drive to whatever speed is safe. I believe people think this system is more advanced than it is. Mine is always set to "Auto"
When you move the selector to "Auto" all you are doing is allowing the drive system to move the car into four wheel drive when it reaches the programed parameters. it was a nifty system to upgrade the truck in an attempt to compete with Grand Cherokees and other vehicles with more advanced systems - the more advanced systems require no input for normal 4wd operation -- they are really all wheel drive.
When you move the selector to "Auto" all you are doing is allowing the drive system to move the car into four wheel drive when it reaches the programed parameters. it was a nifty system to upgrade the truck in an attempt to compete with Grand Cherokees and other vehicles with more advanced systems - the more advanced systems require no input for normal 4wd operation -- they are really all wheel drive.
Re: Vibration / Grinding in Auto Mode
okay bottom line is that when the Truck is in 4x4, you're not supposed to be going at high speeds. I went to my Mechanic and i asked him the same question and he told me that if your going at high speeds, and the 4x4 is engaged, you will feel a little grinding.
No need to be worried about it.
No need to be worried about it.
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funnyman82
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Re: Vibration / Grinding in Auto Mode
as far as i know in 2wd and auto, i am able to go any speed and in 4hi and 4lo in lower speeds...is this correct?
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funnyman82
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Re: Vibration / Grinding in Auto Mode
So this noise starts when I get to about 80km/h whether I am in 2wd or auto and continues past that. It is not as bad in 2wd as it is in auto.. Can anyone suggest anything? I don't want to ruin anything because of this... Thx!!
Re: Vibration / Grinding in Auto Mode
Since your original post indicated that by moving the switch to 2WD eliminated the noise -- One would think it had to come from the front drive system or the transfer case. SInce on dry pavement the auto is actually in 2WD - if it changes the sound to move it to 2WD -- then the transfer case must be doing something it should not.
But now you are saying it is occurring in 2WD also -- If this is true it could be any number of suspension wheel parts causing this. Do you feel it more at one wheel -- like a wheel bearing?
Have you done any checking on the operation of the systems -- any leaks noticable on the trans/transfer or differentials.
But now you are saying it is occurring in 2WD also -- If this is true it could be any number of suspension wheel parts causing this. Do you feel it more at one wheel -- like a wheel bearing?
Have you done any checking on the operation of the systems -- any leaks noticable on the trans/transfer or differentials.
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funnyman82
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Re: Vibration / Grinding in Auto Mode
I havent seen any leaks so far. The noise seems like it is coming right from below where i am sitting so just below the driver / passenger seat area. Does this help?
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funnyman82
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Re: Vibration / Grinding in Auto Mode
Thank you for your reply! What can cause the u joint to fail? What does a good u joint and a bad u joint look like? Can I just look at it? Thx!
Re: Vibration / Grinding in Auto Mode
It does not sound as if you have had this looked at on a lift? That's the first thing you do!
If any of the u joints or CV joints are bad any competent mechanic will be able to see them -- as well as any problems with the mounts.
If any of the u joints or CV joints are bad any competent mechanic will be able to see them -- as well as any problems with the mounts.
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funnyman82
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Re: Vibration / Grinding in Auto Mode
What is approximate cost for changing these? Thx!
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fleurys
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Re: Vibration / Grinding in Auto Mode
do your homework a bit here.. I gave you a link that points you in the right direction....funnyman82 wrote:What is approximate cost for changing these? Thx!
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asnorton44
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Re: Vibration / Grinding in Auto Mode
Front UJoint P#37126-01G25
Approximate time to complete is 1.5 hours.
Approximate time to complete is 1.5 hours.
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funnyman82
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Re: Vibration / Grinding in Auto Mode
thank you asnorton44 for the part number. Will this be the same for the front and back? As fleurys had posted there are two different ones, one for the front and one for the back.
The prices seem reasonable at theujointstore.com website. Also at that site they have only a 1-0049x part and not the 1-0049. Would they be the same? And what is the difference between the 1-0029 and 1-0029bf? (Found it...heavier duty for rear end) How many of the u-joints do you need? Neapco website eludes to 1xfront and 2xrear...
Also wanted to find out if it is something I can do myself. I tried looking in the service manuals on this site and couldnt find it and didnt know which section to look into. If someone could point me in the right direction, it would be appreciated.
Thank you everyone for your help!
The prices seem reasonable at theujointstore.com website. Also at that site they have only a 1-0049x part and not the 1-0049. Would they be the same? And what is the difference between the 1-0029 and 1-0029bf? (Found it...heavier duty for rear end) How many of the u-joints do you need? Neapco website eludes to 1xfront and 2xrear...
Also wanted to find out if it is something I can do myself. I tried looking in the service manuals on this site and couldnt find it and didnt know which section to look into. If someone could point me in the right direction, it would be appreciated.
Thank you everyone for your help!
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asnorton44
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Re: Vibration / Grinding in Auto Mode
No front and back are different.
Back is part # 37126-VB925. Time to complete the back is 1.7 hours.
Back is part # 37126-VB925. Time to complete the back is 1.7 hours.
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funnyman82
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Re: Vibration / Grinding in Auto Mode
So I was able to drive highway speeds today and have the same noise in 2wd mode as well.. Would it still be ujoints?
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funnyman82
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Re: Vibration / Grinding in Auto Mode
I would not plan on replacing a part just because someone on a forum says you need "u joints".
You need to take the truck to a knowledgeable mechanic so they can drive the vehicle and experience the noise/vibration --- and put it back on a lift to have a look at everything again. You do not know enough about the vehicle to fix this.
This is obviously making enough of a noise/vibration that your are concerned about it - It could be something minor - but you do not want something that could have been easily fixed turning into an expensive repair. My local mechanic changed both my differentials/ transmission/ transfer case/ and engine oil for $90.00 labor + the oils and filter. Trust me if you need to service the fluids -- its not worth doing it yourself.
Also - you do not say how many miles on the truck - Wheel bearings and driveshafts normally last a long time -- but if you have 175-200k on the truck anything could be going.
You need to take the truck to a knowledgeable mechanic so they can drive the vehicle and experience the noise/vibration --- and put it back on a lift to have a look at everything again. You do not know enough about the vehicle to fix this.
This is obviously making enough of a noise/vibration that your are concerned about it - It could be something minor - but you do not want something that could have been easily fixed turning into an expensive repair. My local mechanic changed both my differentials/ transmission/ transfer case/ and engine oil for $90.00 labor + the oils and filter. Trust me if you need to service the fluids -- its not worth doing it yourself.
Also - you do not say how many miles on the truck - Wheel bearings and driveshafts normally last a long time -- but if you have 175-200k on the truck anything could be going.
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funnyman82
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Re: Vibration / Grinding in Auto Mode
just an update, i took my qx4 to the mechanic last week and he said that my tires were pretty worn, which i knew needed changing soon. He said maybe because of that i may be getting the vibration.. what do you guys think?
thank you!
thank you!
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Buzzman
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Re: Vibration / Grinding in Auto Mode
Had a similar problem/noise on one side earlier this winter. Turned out to be nothing more than a bad wheel bearing. Fairly cheap fix.
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donald
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2010 Pathfinder LE - Location: Elk Grove, CA
Re: Vibration / Grinding in Auto Mode
I'd like to know how difficult this is too?funnyman82 wrote:...
Also wanted to find out if it is something I can do myself. I tried looking in the service manuals on this site and couldnt find it and didnt know which section to look into. If someone could point me in the right direction, it would be appreciated.
Thank you everyone for your help!
In looking at the courtesynissan.com parts photo of the propeller shafts:
It looks like you just release it from the 4-bolts on each end of the two shafts, and the 2 shafts should drop out.
But as it is with everything, I'm assuming this is no simple task since I'm reading it takes 1.5hr for a competent/trade mechanic to do this.
My first concern is reach the bolts that are "cornered" in, or maybe unreachable
due to weird angles.what say you?
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donald
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2010 Pathfinder LE - Location: Elk Grove, CA
Re: Vibration / Grinding in Auto Mode
I can understand your point about not attempting something you're unsure about only to cause more damage or further complicating the repair.yeldogt wrote:I would not plan on replacing a part just because someone on a forum says you need "u joints".
You need to take the truck to a knowledgeable mechanic so they can drive the vehicle and experience the noise/vibration --- and put it back on a lift to have a look at everything again. You do not know enough about the vehicle to fix this.
This is obviously making enough of a noise/vibration that your are concerned about it - It could be something minor - but you do not want something that could have been easily fixed turning into an expensive repair. My local mechanic changed both my differentials/ transmission/ transfer case/ and engine oil for $90.00 labor + the oils and filter. Trust me if you need to service the fluids -- its not worth doing it yourself.
Also - you do not say how many miles on the truck - Wheel bearings and driveshafts normally last a long time -- but if you have 175-200k on the truck anything could be going.
However, this is why we have the input of the forum or other experienced people who might have done this in in their R50 ownership lifetime.
Just like the above u-joint question, if it is really as simple as dropping the propeller shafts, snapping out the u-joints, and replacing... I'm gonna do it myself, despite labor costing 1.5hr x 60-100$/hr (total 90-150$ labor).
I do agree with you that the truck needs to be taken in to make sure it's the u-joints, or perhaps the wheel bearings that are causing the vibration/sound.
You don't wanna spend ~25$ per NeapCo u-joint (making that 100$ parts cost) only to find out your vibration/sound still exists. That means you technically threw out a u-joint or wheel-bearing that was still good, only to spend MORE money in continuing tracking down the root-cause.
However, if it's easy to drop the propeller shaft and to remove the u-joints, it doesn't cost much to drop it and personally inspect the u-joint for any significant spindle/bearing wear.
And I don't understand why you would say it's not worth changing out fluids yourself?
why not? I know theres always the arguement "my time is worth more than the mechanic's", but for the weekend-warrior or the common garage-wrencher at home, it's not all that bad. Sure, $90 may not be a wallet-breaker, but if you do it yourself, you save that $90.
And sorry for the sidetrack
... back on topic 
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donald
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2010 Pathfinder LE - Location: Elk Grove, CA
Re: Vibration / Grinding in Auto Mode
Ok... so it looks like it's gonna be a moderately difficult feat just to remove the U-joints themselves.
Watching some youtube videos on how to do this, I'm guessing that 10year old u-joints are not going to be anything "easy" to just pop out anytime I want
Removing the propeller shaft from Axle flange
http://youtu.be/eWYNfVdAx70
Removing just 1 U-joint from the joint
yikes
http://youtu.be/vU9aRWHXweU
This is the "nice" way to remove a U-joint
http://youtu.be/2_iZ2jRHK3A
So, since I don't have a vise, nor the money to buy a specialty U-joint removal tool, nor an impact wrench... seems like I'd be doing a whole lot of "banging".
I may consider taking the U-joints for a mechanic to deal with :P
Watching some youtube videos on how to do this, I'm guessing that 10year old u-joints are not going to be anything "easy" to just pop out anytime I want
Removing the propeller shaft from Axle flange
http://youtu.be/eWYNfVdAx70
Removing just 1 U-joint from the joint
yikeshttp://youtu.be/vU9aRWHXweU
This is the "nice" way to remove a U-joint
http://youtu.be/2_iZ2jRHK3A
So, since I don't have a vise, nor the money to buy a specialty U-joint removal tool, nor an impact wrench... seems like I'd be doing a whole lot of "banging".
I may consider taking the U-joints for a mechanic to deal with :P