Wierd rear end vibration and noise while turning

[junehhan]

Hey guys, I just got back from a trip and my rear end seems to be doing something wierd. As I got home, my rear end started making a wierd vibration and rubbing noise everytime I made a sharp turn while accelerating. I just went out and tested it again, and it only does it when you are giving the car gas while doing a sharp turn. I found an empty parking lot to make a few sharp turns, and it goes away as soon as I release the gas pedal, only to start again as soon as i'm back on it no matter how lightly while turning. Any idea's? I had the rear differential fluid changed a bit ago to Amsoil Series 2000 75w90 like the manual explains. Since Amsoil's Series 2000 gear lube already comes with the limited slip additive, I did not add any limited slip additive since Amsoil says that it's not needed(my old Lightning didn't need it either). Right after the fluid change, I tested it by driving in tight circles, and it never had a problem till now. Any idea's?????????

[FordNut]

Hey guys, I just got back from a trip and my rear end seems to be doing something wierd. As I got home, my rear end started making a wierd vibration and rubbing noise everytime I made a sharp turn while accelerating. I just went out and tested it again, and it only does it when you are giving the car gas while doing a sharp turn. I found an empty parking lot to make a few sharp turns, and it goes away as soon as I release the gas pedal, only to start again as soon as i'm back on it no matter how lightly while turning. Any idea's? I had the rear differential fluid changed a bit ago to Amsoil Series 2000 75w90 like the manual explains. Since Amsoil's Series 2000 gear lube already comes with the limited slip additive, I did not add any limited slip additive since Amsoil says that it's not needed(my old Lightning didn't need it either). Right after the fluid change, I tested it by driving in tight circles, and it never had a problem till now. Any idea's?????????Put some additive in and see if it fixes it.

[jgc61sr2002]

Sounds like the limited slip differential clutches. Sounds like a trip to the dealer is in order. Good luck. Keep us posted.

[junehhan]

I don't think I like the sound of that. I'll try some additive first, but wouldn't it be chattering instead of making a rubbing type vibration if it needed the additive? Also, if it was the additive, wouldn't it be doing this even when i'm not giving it gas while going around a sharp corner?

[Marauderjack]

Might be that the Amzoil has "almost enough" additive and just a dab more will fix it!! Get a bottle of the Ford "stinky stuff" and I'll bet it will be fine!! :up:

Marauderjack :pimp:

[RoyLPita]

Rear end chatter ofter a long highway trip is normal.

[TheDealer]

Take it back to the dealer and get it checked. Could be worn axles. RAY

[sailsmen]

I thought the additive was a friction enabler. No additive and the clutches would slip.

I don't think you have slipping clutches. But I don't know.

[TripleTransAm]

The clutches are supposed to grab, but not excessively... so the friction modifier serves to decrease the amount of friction, just enough to allow proper grabbing when the axles are meant to be 'tied' together, but during cornering, once the clutches break grip, they are then supposed to slide easier, until they get to grip once again, and then it's right back to a good amount of hold.

Tough to describe, but look at it this way:

There are two kinds of friction, static and dynamic. Static is when the two surfaces are stationary with respect to each other (ie. no rubbing, otherwise known as a very boring first date). Dynamic is the friction that occurs when the two surfaces are in movement relative to each other. A good example is pushing hard on a big appliance trying to get it to move... getting it to move involves overcoming the static friction, and once you get it moving, you just have to apply enough force to overcome the dynamic friction. Dynamic friction is less than static friction, in this case.

I suppose that in the case of a limited slip additive, it must change the dynamic friction such that once the clutches ARE slipping, they don't try too hard to grab (ie. much lower dynamic friction) because if they did, the action would be very jerky. Once the two axles are back to equal speeds, the good static friction qualities will hold them there until they are overcome yet again during the next turn.

Since the clutches are soaked in the diff oil (+additive, if that's the case), any deviation from the factory spec will make the clutch material behave differently, and then it's trial and error before you find the good ratio.

[junehhan]

Thanks for the advice and help guys. I've got a 4oz bottle of differential limited slip friction modifier and i'll try half of the bottle first. Today on my way to work, it doesn't seem to be as bad as it was yesterday, although it's still doing it. It seems to do it a bit more when i'm accellerating while making a sharp right turn vs. a sharp left turn. I'll probably put 2oz of the additive in on Thursday since i've got no time till then............

[Ross]

[QUOTE=junehhan]Hey guys, I just got back from a trip and my rear end seems to be doing something wierd. [QUOTE]


Did you go to Mexico? :lol:

[RoyLPita]

This is from the 2004 Ford Crown Victoria, Grand Marquis, and Marauder shop manual:
"With the Traction-Lok differential axle, slight chatter noise on slow turns after extended highway driving is considered acceptable an has no detrimental effect on the locking axle function."

[junehhan]

This is from the 2004 Ford Crown Victoria, Grand Marquis, and Marauder shop manual:
"With the Traction-Lok differential axle, slight chatter noise on slow turns after extended highway driving is considered acceptable an has no detrimental effect on the locking axle function."


Hey, thanks for that tip. In my case, it's more of a rubbing/moaning sound than a chattering though. You can kinda feel this rubbing type sensation from the rear end too, usually while making a sharp right turn while hitting the gas pedal. It's still doing it slightly right now, but i'll see what happens after I add 2-3oz of the limited slip additive. When I have the 4.10 gears put in sometime this summer, I think i'm just going to have full synthetic Motorcraft gear lube put in instead just to prevent this since apparantly not all LSD's respond the same to the Amsoil gear lube. I remember when I had the diff fluid changed on my old Lightning, it worked fine on the Amsoil gear lube without having to add anything extra in............

[TripleTransAm]

In my case, it's more of a rubbing/moaning sound than a chattering though. You can kinda feel this rubbing type sensation from the rear end too,


Hot DANG... I think I'm gonna call the missus and see if she wants to come home early today *nudge nudge wink wink*...

[TAF]

Hot DANG... I think I'm gonna call the missus and see if she wants to come home early today *nudge nudge wink wink*...
You're a sick man /Steve....but, that's what I like about you....

[David Morton]

I suppose that in the case of a limited slip additive, it must change the dynamic friction such that once the clutches ARE slipping, they don't try too hard to grab (ie. much lower dynamic friction) because if they did, the action would be very jerky. Once the two axles are back to equal speeds, the good static friction qualities will hold them there until they are overcome yet again during the next turn. That's exactly the way they explained it to me at the GM training school in Atlanta 12 years ago. Sticky when static, slippery when dynamic.

You figure all that out by yourself? What's your MM rating? I'll recommend you for OTS. :D

[TripleTransAm]

You figure all that out by yourself? What's your MM rating? I'll recommend you for OTS. :D


Okay, you got me... I searched high and low for what OTS could possibly mean and came up with this... http://www.ots.duke.edu/ ;)

And MM rating... well, I have ONE Marauder... does that give me a MM rating of 1?
:rock:

[junehhan]

Hot DANG... I think I'm gonna call the missus and see if she wants to come home early today *nudge nudge wink wink*...


LOL, I don't think I want to know what you are trying to imply there..........

[junehhan]

Well, I had the limited slip friction modifier put in this morning, and it's still doing it. It seems to do it more when i've come to a complete stop, and accelerate as i'm turning. Should I give it a little more time, or should I go ahead and schedule another appointment with the dealership?

[David Morton]

Okay, you got me... I searched high and low for what OTS could possibly mean and came up with this... http://www.ots.duke.edu/ ;)

And MM rating... well, I have ONE Marauder... does that give me a MM rating of 1?
:rock:
OTS=Officer Training School

1 Stock Marauder=MM1; add 1 Modification (Performance only)=MM1.1; 2 Stock Marauder=MM2, etc.

:up:

[TooManyFords]

Well, I had the limited slip friction modifier put in this morning, and it's still doing it. It seems to do it more when i've come to a complete stop, and accelerate as i'm turning. Should I give it a little more time, or should I go ahead and schedule another appointment with the dealership?

Give it 3-4 days to work in. When I had this happen after a gear change, it took about that long for the modifier to get 100% into all the clutches and then it quieted down.

John

[junehhan]

Give it 3-4 days to work in. When I had this happen after a gear change, it took about that long for the modifier to get 100% into all the clutches and then it quieted down.

John

Out of curiosity, what was yours doing when you changed the gears?

[TooManyFords]

They didn't put the friction additive in thinking that the lube they installed already had it. After a few days, I was getting chatter and grinding noises as I turned corners at low speeds. After adding it, it quieted down and I haven't heard a peep out of it.

John

[junehhan]

They didn't put the friction additive in thinking that the lube they installed already had it. After a few days, I was getting chatter and grinding noises as I turned corners at low speeds. After adding it, it quieted down and I haven't heard a peep out of it.

John


I'm not getting chatter, but I am getting grinding and moaning noises. Thanks for letting me know, and i'll give it another couple days of driving. Out of curiosity, where you also feeling a vibration as well from the rear end?

[CRUZTAKER]

Glad to hear you are making headway Junehhan.

My gears made a slight hum for a few hundred miles and quieted down over time. I have heard from mechanics however, that if the gears weren't installed just right, (they use a micrometer and a yellow paint stick to check for proper mesh), that you may experience noise and such, and the gears will need to be re-adjusted.

I am not a motorhead and do not know the proper terms for what I am trying to say...maybe some else can explain further.

[looking97233]

Just a thought, maybe the amsoil is working better than the stock fluid... maybe you are slightly spinnig the inside tire when under power and turning, as the clutches may be sticking together better?

[TripleTransAm]

I am not a motorhead and do not know the proper terms for what I am trying to say...maybe some else can explain further.


I think you said it just perfectly...

[TripleTransAm]

Just a thought, maybe the amsoil is working better than the stock fluid... maybe you are slightly spinnig the inside tire when under power and turning, as the clutches may be sticking together better?

For the clutches to be sticking better, they'd have a harder time releasing grip from each other. And the release would be more violent. And/or they would occasionally chatter from the momentary occasions where they would actually grip and then let go.

Whenever I've had diff fluid / additive problems, it's usually been a case of groaning... not unlike what you would hear from a noisy dry hinge (creak) on a house door, except that it would be much deeper in tone and more metallic/hollow.

Whine or howl when turning, you'd have to think of why this would happen when turning... usually this is a sign of misadjusted gears as Barry mentioned, but the question is which gears? If it's not the pinion versus ring contact (which would be audible even when going straight), it would have to be a set of gears that only act when you're turning. And these are located WITHIN that hollow shell that you see when you pop the diff cover... it's this hollow shell (carrier?) that has the small gears that permit the different axle speeds... could be the gears on the ends of the axles as they mesh with the other idler gears, since there is only movement between these two when the speeds are different between each axle. Otherwise, the carrier housing applies equal force on both axle gears through each idler gear.

Here's a good set of pages describing what happens when you turn.
http://auto.howstuffworks.com/differential.htm
(just took a look at the site... replace 'idler' in my description by 'pinion' although they mean the small pinion gears, not the big mofo at the transmission shaft - the 3rd page is really good at illustrating a turning car)

So in short, maybe the pinion gears or axle gears are the problem?

[junehhan]

Thanks guys for your help. It didn't go away, so I made an appointment with my stealership's service department. Bottom line, is that the blokes who work there are telling me that it's normal. I've just lost any faith i've had in them again as if this was normal, it would have done it when I first bought the car. It is more like a groan as Steve just described. When I confronted them on how this was normal, they told me that it's just normal clutch action on the differential and that they get noisy over time. I've pretty much had it with these guys, and the only reason I keep going back to them is because I am hoping they will somehow become competant one day. I would have asked for the manager of the service department, but he was on the phone cussing someone out so loud, everyone could hear and was staring at him. Right before he slammed the phone on someone, he was accusing them of "bull****" or something like that. I figured with the service manager so angry at someone, I better avoid him.

[Marauderjack]

june....

After all you went through to get the car.....YOU SURE HAVE HAD A BUNCH OF PROBLEMS!!!!!

May be time to pursue the "Lemon Law" and push for a new car while they still have some....Just a thought?? ;)

My car has been perfect from day one and it was built about the same time as yours....November 03??

I feel for ya man!! :(

Good Luck!!

Marauderjack :up:

[427435]

If this problem started shortly after putting the Amsoil in, why not just drain the Amsoil and put in the specified Ford oil? Even then it might take a while to clear up as the clutches now have a coating of the Amsoil on them. Taking the diff cover off and spraying some parts cleaner on the diff might speed up things.

Limited slip clutch packs and the oil (with friction modifiers) can be a delicate combination. I would recommend getting back to Ford specified lubricants here.

[junehhan]

Yeah, i'm actually considering doing that just to see whether there is any difference. However, i've used this same Amsoil Series 2000 75w90 gear lube in other vehicles with the Ford traction-lok differential without any problems, and didn't even need to use the friction modifier additive in those cases. I used it in my old 01 Cobra, the 02 Lightning, and my Crown Vic with no problem, although I believe the 00 Crown Vic used a standard open differential. I figure if anything, this will give me peace of mind and help me eliminate the possibilities and ultimately narrowing down to what it could be.


Jack, the problem here is not the car. The problem, is with people who offer crummy service, and don't give a care about you by providing less than the bare minimum they need to. My problems are actually pretty minor as I have the ticking which it appears a few of the people have. As far as the a/c clutch chirping goes, it was fixed by having the shims reseated which is also minor. As far as the moulding goes that needed replacing, that's pretty minor as well. Once I figure out why i'm getting this moaning type noise from the rear end, and Ford releases a fix for the ticking issue, i'll be set and happy once again :) Trust me, it may seem like i've had problems, but you don't know what problems are until you've owned a Land Rover product.

[Marauderjack]

I have a friend that has a Land Rover and he spent $1700.00 on a 100K mile tune-up.....He said NEVER AGAIN!!!

I hope you get the rear end as well as the ticking fixed to your satisfaction!! I had a high mileage CV (200+K) and the axles were ruined by the bearings!! It sweems Ford has had a bunch of "soft" axles since the Ford dealer in Charleston had 24 sets in stock for police vehicles!!! That ought to tell ya something!!

Good luck with your dealer!!

BTW....My dealer agreed to replace my rear tires under warranty over a month ago and still hasn't gotten the tires?? They say they are back ordered.....I can get them from Tire Rack in 2 -3 days??? Go Figure!!??

Marauderjack :(

[junehhan]

What kind of Land Rover does your friend have?

[Marauderjack]

It's the small one......I don't know much about them and really don't want to!!! :nono:

It supposedly has a BMW V8 engine and leaks badly!! :flamer:

Marauderjack :)

[junehhan]

It's the small one......I don't know much about them and really don't want to!!! :nono:

It supposedly has a BMW V8 engine and leaks badly!! :flamer:

Marauderjack :)


Jack, your description doesn't help me as all Rovers always leak. As far as the engine goes, Land Rover just started using a brand new BMW V8 starting with the 03 redesigned Range Rover, which has a 4.4 litre BMW V8 making 282hp. If it's an older one, then it's likely the 3.9, 4.0, or 4.6 litre Land Rover V8 which is based on the old Buick V8 engines which I believe originally displaced 3.5 litres. It would either be a Range Rover, Discovery, Discovery Series II, or Defender 90. It probably isn't a D110 since those are really big and super rare. Both of my Land Rover products i've owned were always leaking something, although the new Range Rover looks promising if you have $75k :)

[Marauderjack]

It's a Discovery......Probably late 90's??

FUGLY......I wouldn't have one at any price!!! :fire: The guy is trying to get rid of it .....Says it is dangerous at highway speeds in the wind (wanders everywhere) and useless as a truck!! :cry:

It is actually a very small station wagon......HOW DO THEY KEEP SELLING THIS STUFF??? :o

Marauderjack :pimp:

[junehhan]

I have to differ with you, because I think the Discovery is the best looking SUV on the market. It looks like a genuine Safari rig, and it's offroading capabilities are unmatched by anything else in it's class. It is one beefy SUV that was designed well for it's purpose, but not built well at all. Land Rover sells these Disco's exactly because they like it's charm, or like the Hamptons status symbol that is associated with it. They were designed more with offroading in mind, not on-pavement driving. If you were to ever take one offroad, you would find new-found appreciation for it as it's just amazing.

[junehhan]

Well, my Marauder is going in to the local SVT dealership tomarrow to have the rear end differential fluid changed again. I'm going to have them change it using full synthetic Motorcraft gear lube to see if that solves the problem. If not, then i'll probably set up an appointment to have this dealer take a look at it since they are a great dealership, unlike the excuse for a stealership my selling stealership is. I think from now on, i'm going to just let my favorite local dealership do my maintenance anyway, just to simplify things.

[junehhan]

Well, my Marauder is going in to the local SVT dealership tomarrow to have the rear end differential fluid changed again. I'm going to have them change it using full synthetic Motorcraft gear lube to see if that solves the problem. If not, then i'll probably set up an appointment to have this dealer take a look at it since they are a great dealership, unlike the excuse for a stealership my selling stealership is. I think from now on, i'm going to just let my favorite local dealership do my maintenance anyway, just to simplify things.

Well, I had the differential gear lube changed Saturday at the SVT dealership to fully synthetic motorcraft fluid along with Ford's friction modifier additive. It took a day, but the rear end is now smooth as butter once again. I know that there are a couple people running Amsoil gear lube in their differential, but apparantly mine didn't like it too much. Boy was that Motorcraft lube expensive though!!!

[Marauderjack]

june.....

Why don't you just use regular old 85W90 with the Ford FM and change it more often??

Dennis Reinhart was not too enthusiastic about synthetics for the rear end and the cost was the deciding factor for me......Sometimes price doesn't equate to the perceived quality or benefit!!?? :down:

I had over 200K miles on my 2000 CV before the axles were replaced and I still think they were the "soft" ones that Ford has been installing?? :confused: I only used the standard lube and changed it every 50K miles....It never looked bad or had an abnormal amount of metal on the magnetic plug until I noticed the roaring noise above 50 MPH......New axles and bearings and all was OK!! :up:

BTW...The guy who rebuilt the rear end didn't think synthetics were worthwhile either??

Glad yours has quieted down.....You had me listening real close to mine too!! :eek:

Marauderjack :D

[junehhan]

Jack, the Marauders come from the factory filled with synthetic gear lube if i'm correct, which is as good enough of a reason as I need to stay with a synthetic gear lube. If it's good enough for factory fill, then it's definately good enough for me. Besides, a high quality synthetic will reduce friction and reduce heat as a result.

[fastcar]

Friends, since I installed the 4.10s a few weeks ago, I have had the same grating/moaning/rubbing noise/sensation from the rear end under throttle from dead stand still taking sharp left or right hand turns.

QUESTION: IS THIS A PROBLEM? Amsoil says that you don't need the friction modifier, but that if you want it, you can add it. They sell a synthetic version that can be used in conjunction with their lubricants.

My question is, does it matter if it moans/rubs?

I asked the mechanic. He said 'No'. He said that the additive was developed to address the bad aesthetics. Your average Joe or Jane won't be comfortable with the noise, and will bring the car back for service. So, they use additives from the factory to get rid of the sound.

Is this true, or does the additive prolong clutch life?

By the way, my old clutches that had 100,000 miles on them with the original, factory lube looked ALMOST NEW. I don't think the previous owner ever engaged them!

Back to the subject: I'm wondering who to believe about the noise. It seems to me that my clutches must be feeling the pressure, because they are moaning without the friction modifier. Shouldn't they wear out quicker, if they are grating like that?

At the same time, how can they work properly, if they are made so slippery that they don't grab one another? I certainly do love the way they work ;)

Any input you guys can give me I'd very much appreciate. Happy 'rauding!

fastcar:burnout:

[Marauderjack]

Fast Forward 3 years, 2 months and 2 days....or so!!??:eek:

Put the FM in and forgedaboudit!!:beer:

Marauderjack:burnout:

PS: Them there Rovers are still FUGLY!!!!:mad2:

[fastcar]

I know, I'm a relentless inquisitor, and learner. I'm trying to find out if it's NECESSARY, or just for aesthetics.

I think this is a worthy question for those who are mechanically inclined or interested.

I like the idea of it being 'grabby', and will live with it if it won't get ruined.

fastcar:burnout:

[Marauderjack]

It is hard on your tires and drive train innards to hop and chop around corners!!:argue:

Using the FM does not diminish performance in any way.....just use it and be happy you have a nice car to use it in!!:D

Marauderjack:burnout: