Excess gear whine from transaxle

[Beez]

2 days ago my 2200 mile '06 started making a new noise I need to figure out asap - booked for local track day this Friday, then Rally in 2 weeks.

The noise is rotational and wheel speed dependent, not rpm. Easiest to hear around 45 - 55 mph. The tone of the whining/whirring noise seems similar to tire noise, but there is zero change in the noise when I change from one road surface type to another. Tires are new Bridgestones, this noise wasn't there for the first 600 miles on the tires. So I don't think it's tires.

Hopefully a helpful clue is that I can control the noise with feathering the throttle. Meaning if I am going between 45- 55 mph, if I give a trace of throttle the noise gets louder, then if I coast it quiets til I touch the throttle again. If I stay in throttle or stay in coast, it is less apparent then just barely going back and forth between the two. Wiggling the steering side to side doesn't seem to make much difference.

From inside the car, very hard to state directionality. I just bought a Go Pro to help trouble shoot. I started placing it inside the front susp area pointing at each hub, didn't pick up a thing. The GoPro easily picks up the sound mounted anywhere in the engine bay. Seems a trace louder pointed at the rear passenger hub as opposed to the rear driver hub. Then I mounted it on the outside fenders of the car, pointed at the rear hubs. Can just barely hear the sound on pass side, can't hear a thing from the outside on the driver side.

After highway driving for an hour, the wheel over the suspected hub doesn't feel any hotter than the other wheels.

Here is a you tube clip with the camera mounted above the pass side rear axle. between :09 and :30 I am "feathering" the throttle to make the sound go off and on:

[video]https://youtu.be/bA0H-7P12S4[/video]

Questions:

So given its road speed and not tire, what else could be possible besides wheel bearing? Is the transaxle itself the only other candidate?

If you guys think yes wheel bearing, is that as straight forward to replace as it appears in the manual? Basically says just remove the caliper, remove a few bolts that hold the hub/bearing assembly, and put on the new one. Any cautions about doing that myself at home?

Since it just started doing this, and the wheel doesn't feel hot from it yet, what are opinions about going ahead and trying to do my track day before repair, or would that be a bad idea?

Thanks a million, Beez

 

[MarkH]

Here is an idea of what it could be. Kevin Kesterson with M2K was watching the video and here is what our thoughts are. It sounds like when the ring and pinion in a regular rear end is bad. It's like when your getting on and off the gas the noise is changing. It could either be the ring and pinion or one of the bearings on the carrier is bad which is causing the mesh between the ring in pinion to not be correct.

Sure hope its not the tranny but from the sound of it there is that possibility. Please post up when you know for sure but in going through a bunch of these transmissions there is no simple fix to them without parts.

Mark Heidaker
M2K Motorsports, LLC

 

[Sinovac]

Have you felt the hub itself rather than the wheel? In my experience a failing wheel bearing will generate more heat. Have you checked the torque on the rear retaining nuts? Any play in the wheels with the car off the ground?

 

[Beez]

Mark, I very much appreciate you and Kevin spotting this. Kevin may have recognized me/the car as a customer of yours from 6 months ago.

My brother-in-law, who has been a senior tech at Lexus for over 25 years just read the post and listened to the video, and he said exactly what you just did - ring/pinion/transaxle. Yes the noise is much worse on throttle, lets up off throttle - he said he doesn't see that feature with wheel bearings.

He suggested drain the trans fluid and look for metal shavings. I won't be able to do that til the weekend. I did just check the transaxle fluid fill plug - full and clean/clear on the finger tip. Have receipt that the fluid was changed at a Ford dealer 3 years/ 1k miles ago.

I think I'll message Kevin for any other ideas on what to check next.

Has anybody heard of this kind of problem, but especially on a always babied and maintained ultra-low mileage car??

Depressing to say the least. I don't have a good feeling about my local Ford dealer. Wonder if I'll end up shipping it back to M2K.

Here is an idea of what it could be. Kevin Kesterson with M2K was watching the video and here is what our thoughts are. It sounds like when the ring and pinion in a regular rear end is bad. It's like when your getting on and off the gas the noise is changing. It could either be the ring and pinion or one of the bearings on the carrier is bad which is causing the mesh between the ring in pinion to not be correct.

Sure hope its not the tranny but from the sound of it there is that possibility. Please post up when you know for sure but in going through a bunch of these transmissions there is no simple fix to them without parts.

Mark Heidaker
M2K Motorsports, LLC

 

[Beez]

Have you felt the hub itself rather than the wheel? In my experience a failing wheel bearing will generate more heat. Have you checked the torque on the rear retaining nuts? Any play in the wheels with the car off the ground?

Yes I felt the sides of the hubs that you can reach through the wheel spokes - all 4 the same and remarkably cool. Haven't checked for play. Checked the wheel lugs , let me know if that is not what you mean by rear retaining nuts.

 

[nota4re]

I unfortunately have to agree with Mark in that the odds are that it is internal to the transaxle. Feathering the throttle really shouldn't make a "load" change to a wheel bearing and, as such I wouldn't expect a wheel bearing to change tone.

Let's try to eliminate some other basics. Inspecting the heat shields on the lower side of the halfshafts where they attach to the transaxle, are they clean from any oil? What is the maintenance history on the transaxle? Last time fluid was replaced? Who replaced the fluid.... and are we 10,000% positive the RIGHT fluid was used?

 

[NorthwoodGT]

Here is an idea of what it could be. Kevin Kesterson with M2K was watching the video and here is what our thoughts are. It sounds like when the ring and pinion in a regular rear end is bad. It's like when your getting on and off the gas the noise is changing. It could either be the ring and pinion or one of the bearings on the carrier is bad which is causing the mesh between the ring in pinion to not be correct.

Sure hope its not the tranny but from the sound of it there is that possibility. Please post up when you know for sure but in going through a bunch of these transmissions there is no simple fix to them without parts.

Mark Heidaker
M2K Motorsports, LLC

after listening to it, I think Mark is correct. sounds like the ring and pinion coming on and off of load. simple thought but have you checked the transmission fluid level? the Ricardo is a oil pump driven transmission that transfers fluid from the back half to the front half. slightly low levels can cause noise plus a good time before running on a track. I'd pull the belly pan and check the level before I would do anything else or even drive the car anymore. I have hubs in stock below dealer cost if you need one. let me know. scott

 

[nota4re]

Beez, while you are answering that last post, I might suggest that you see if the transaxle fluid can tell you anything. (Not sure if you do your own maintenance or not.) If your car was in our shop, I'd drain the fluid and see what it looked like and what it smelled like. (If you didn't do the last transaxle fill yourself, I'd start by checking the level before I drained it - just to see where it's at.) Also, see what's on the magnetic plug on the passenger side of the transaxle. Generally this magnet is pretty ugly at the first maintenance and much better after that. Pics can help us know if what you see is "normal".

 

[Beez]

As in post #4, the transaxle fluid currently checks as full, clean, and entirely normal look and smell by dipping a finger at the fill plug. The soonest I might be able to drain it and check the filter/screen on the drain plug is Friday.

The transaxle fluid was last changed 8/2/14 at 1,011 miles (2,200 miles now) at Randall Reed's Park Cities Ford Dealership in Dallas. Ford PN XT-4-QGL (4)

I actually had the belly pans off just 2 days ago doing oil/filter/ brake and clutch fluids. Every square inch of this car, including the underside and entire transaxle, all nearby heatshields etc etc is all immaculate. There is not even a speck of grime anywhere. All the various delicate little paper tags around the engine bay are as brand-new.

..... but in going through a bunch of these transmissions there is no simple fix to them without parts.

Mark Heidaker
M2K Motorsports, LLC

So I did some searches to learn Ford told Ricardo to make zero replacement parts. OMfG, I might need therapy by the time this is dealt with.

 

[nota4re]

Beez - as I suspected, you have the WRONG transaxle fluid in the car.

Ford PN XT-4-QGL

This is a 75w-90 GL4 TRANSMISSION fluid and has no business in a Ford GT TRANSAXLE.

You want XT-75W90-QGT.

I would suggest replacing it immediately but the damage may already be done.... in which case I think the dealership may owe you a replacement transaxle.

 

[BlackICE]

Yikes!

Another example of why I try to avoid taking my FGT to a dealer!

Now I still have to do get my air bags replaced. I'm possibly driving with a bomb.

 

[Beez]

This is a 75w-90 GL4 TRANSMISSION fluid and has no business in a Ford GT TRANSAXLE.

You want XT-75W90-QGT.

I would suggest replacing it immediately but the damage may already be done.... in which case I think the dealership may owe you a replacement transaxle.

Kendall, I did not suspect such critical information would be identified by simply reading a PN off the old receipt. Thank you so much for catching this seeming minutiae. Can you or anyone else speculate as to what this wrong fluid would do?

I can only start to imagine the dealer's response to a 3 year old receipt from 2 owners ago. I'm sure I'd have to lawyer-up.

 

[nota4re]

Beez, first off, I am very sorry for the situation that you are in. I'm glad that we can get down to the root of the problem that was clearly bothering you..... not that you're that much better now!

The fluid that was added by the dealer is clearly not GT-spec. I'm sure that it was a genuine accident - and likely too easy to do. However, for certain it is THEIR bad and you, like most GT owners, don't accumulate that many miles per year so you shouldn't feel guilty that the symptoms took 3 years to manifest. I think it is unlikely that you will find someone who could describe with any accuracy what could have been the detrimental damage to the transaxle. Frankly, what concerns me the most is that allegedly this noise just started to appear - as opposed to being present from day 1 of the incorrect fluid change. That would lead me to believe that there has been some kind of inappropriate wear internal to the transaxle. In layman's terms, the fluid properties themselves haven't caused the noise and the fact that the noise has occurred over time is therefore of concern.

As you have discovered, there is no repairing a GT transaxle. It's simple an R&R swap. The good news is that there are plenty of them available. (And for a GT-knowledgeable shop, swapping one out can be done in a day.)

My recommendation would be that you approach the Ford dealership - perhaps set up an appointment with the GM or owner. You need to have a discussion about what happened - acknowledge that it was likely an easy mistake for a non-GT-oriented shop to make but, nevertheless, it is their responsibility. I think you need to push for an entirely new transaxle.... PERIOD. A friendly, mature, fact-based discussion.

To best protect yourself - in case things go entirely South, I would use a syringe and a tube to pull out a sample of the fluid that's in the car just in case someone says its only the receipt that is wrong.

Wish you the best of luck and if we can help in any way - just let me know. You have my cell in a PM.

 

[PeteK]

If the transaxle fluid is clean, and no metal on the drain plug, then one other thing to check is the CV joints. Those also make noise at wheel speed and the noise changes according to torque load. Have the transaxle flange bolts been updated?

 

[PeteK]

And one other thing: Pull an oil sample and send it to a lab for analysis, BEFORE you let anyone change it. Keep a small sample too.

 

[PeteK]

Also, does the noise change for different gears, or always the same in any gear?

 

[nota4re]

PeteK - I think we know the problem. Read a few posts back.

 

[soroush]

Beez, first off, I am very sorry for the situation that you are in. I'm glad that we can get down to the root of the problem that was clearly bothering you..... not that you're that much better now!

The fluid that was added by the dealer is clearly not GT-spec. I'm sure that it was a genuine accident - and likely too easy to do. However, for certain it is THEIR bad and you, like most GT owners, don't accumulate that many miles per year so you shouldn't feel guilty that the symptoms took 3 years to manifest. I think it is unlikely that you will find someone who could describe with any accuracy what could have been the detrimental damage to the transaxle. Frankly, what concerns me the most is that allegedly this noise just started to appear - as opposed to being present from day 1 of the incorrect fluid change. That would lead me to believe that there has been some kind of inappropriate wear internal to the transaxle. In layman's terms, the fluid properties themselves haven't caused the noise and the fact that the noise has occurred over time is therefore of concern.

As you have discovered, there is no repairing a GT transaxle. It's simple an R&R swap. The good news is that there are plenty of them available. (And for a GT-knowledgeable shop, swapping one out can be done in a day.)

My recommendation would be that you approach the Ford dealership - perhaps set up an appointment with the GM or owner. You need to have a discussion about what happened - acknowledge that it was likely an easy mistake for a non-GT-oriented shop to make but, nevertheless, it is their responsibility. I think you need to push for an entirely new transaxle.... PERIOD. A friendly, mature, fact-based discussion.

To best protect yourself - in case things go entirely South, I would use a syringe and a tube to pull out a sample of the fluid that's in the car just in case someone says its only the receipt that is wrong.

Wish you the best of luck and if we can help in any way - just let me know. You have my cell in a PM.

great advice!

sorry to hear about this as well, I resemble Clinton I never let anyone touch the GT other than
Kevin/mark at m2k occasionally when I have surpassed my level or ability.

 

[junior]

Kendall is the Ford GT Columbo- Good Luck Beez !

 

[2112]

Yikes!

Another example of why I try to avoid taking my FGT to a dealer!

Now I still have to do get my air bags replaced. I'm possibly driving with a bomb.

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