Excess gear whine from transaxle


NorthwoodGT

GT Owner
Jun 12, 2009
1,215
Michigan
notre4 is totally correct. they put in a synthetic gear oil for normal transmissions such as for a Mustang or Shelby. this is not the oil called for (by Ford) for the GT/Ricardo transmission which calls for a "premium" synthetic gear oil. I'd be curious what they charged for the basic oil as compared to the premium oil required. needless to say "KEEP YOUR RECEIPT"
 

MarkH

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
May 19, 2007
528
Katy, Texas
FYI, its not his receipt but a couple of owners ago receipt.

Mark
 

PeteK

GT Owner
Mark II Lifetime
Apr 18, 2014
2,267
Kalama, Free part of WA State
PeteK - I think we know the problem. Read a few posts back.

Yup, I read those and I listened to the sound clip. It sounds like gear whine to me too (much like the M22 manual transmission in a 1964 Corvette I once owned, which was normal for that box), so I agree that very likely it's the transaxle. But just in case the transaxle is not the problem, I'm thinking of other (and less expen$ive) possibilities.

Something about this problem is still bugging me. On a 2200-mile car, with only 1000 miles since the fluid change, I doubt that the wrong gear oil would cause the problem (unless it's been raced for much of that distance). Yes, I know it's possible, but having personal experience with many cars for many years, that just doesn't seem right. Now, after 50Kmi or more, and the transaxle gradually starts making more noise, I could see the the cumulative wear due to the wrong oil could be the culprit, but not likely at this little mileage and usage. I wonder if something slipped out of alignment internally, like the collars that hold the ring and pinion in alignment. If so, it might be possible to adjust out the noise. But, I haven't been inside one of these boxes, and you have, so you would know better than I do about this particular box of gears.
 

MarkH

GT Owner
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May 19, 2007
528
Katy, Texas
If I had my guess at what happened, the fluid could have sped up the process but I am to shocked to see a transaxle with such few miles on it and now the issues you are having. I am wondering if maybe one of the plastic housings that holds the bearings together in the tranny may be failing which we have seen happen in a few of these trannys. I would definitely not be driving it anymore until you can diagnose the problem and find out exactly what is going on inside the car. If for sure it is the tranny, the worse thing is it will need a complete new tranny and Ford has a few in stock but at a very expensive price unfortunately, or MAYBE the tranny can be pulled apart and some parts can be gathered from other broken trannys to fix this one. We have been able to do that on a few occasions but our parts in house are limited as well as where we have been able to source them also.

Thanks
Mark
 

2112

Blue/white 06'
Mark II Lifetime
Is there a requirement for "friction modifiers " on this transaxle like many other Ford 3rd members have?
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,832
Largo, Florida
Is there a requirement for "friction modifiers " on this transaxle like many other Ford 3rd members have?

The friction modifier is required in differentials with clutch packs. The vendors will chime in for sure, but I'm not aware of any manual transmissions/transaxles that require it.
 

nota4re

GT Owner
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Feb 15, 2006
4,176
Not sure of the answer generically, but the GT Transaxle does NOT require the addition of any friction modifiers.
 

nota4re

GT Owner
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Feb 15, 2006
4,176
But, I haven't been inside one of these boxes, and you have, so you would know better than I do about this particular box of gears.

Yes, I have had the benefit of taking a look-see inside the transaxle.... but totally not convinced that this opportunity makes me any more qualified that you or others to comment about how they work!!
 

PeteK

GT Owner
Mark II Lifetime
Apr 18, 2014
2,267
Kalama, Free part of WA State
The friction modifiers are needed for the clutch pack in older style limited slip diffs. The GT differential has a Torsen limited-slip mechanism. No clutch packs.
 

nota4re

GT Owner
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Feb 15, 2006
4,176
Beez,

No doubt your head is spinning right now. I'm sympathetic. I went back and re-read the entire thread.

I stand by my suggestion to approach the dealership who added the incorrect fluid. In the worst case scenario, this fluid may have caused or contributed to the demise of the transaxle itself. You need to inform them to see if they will offer any remedy. (Keep in mind, that you have proof in 1) the receipt with the incorrect oil; 2) a sample of the oil that you extract from the transaxle; 3) your video recordings of the noise.)

In parallel with this activity, I would drain and re-fill the transaxle with the correct fluid. (If you need any, let me know as we generally have a case or two in stock.) Take and share a pic of the magnetic plug on the passenger side of the transaxle and also the screen from the plug on the driver's side. I and/or others can let you know if the appearance is "normal". Drain the fluid (4 quarts) into a clean pan and take a close look at what comes out. Look for any signs of metal flakes. I would leave the pans off of the car and go drive the car a bit (20 minutes or so to let the fluids come up to temp) and then I would come back and drain and re-fill it one more time.

I would like to think think that there's is a better than 50% chance that the noise will disappear. A lubricant with the wrong properties can cause all kinds of odd anomalies - not the least of which is components that should retract from a position and don't or vice versa. These can all contribute to the noises you heard/recorded.

They VERY best outcome from my perspective is that the dealership - with the video evidence that you supply, agrees that their error has jeopardized the transaxle and they will pay all or part of a replacement transaxle. If they do this, I would recommend paying the core charge which allows you to keep the current transaxle.

As FYI, last I checked, dealer cost on the transaxle is approximately $13,500 and there is a $3200 core charge.
 

Beez

GT Owner
Mark II Lifetime
Oct 28, 2016
195
South Denver
Hi guys. Thanks for acknowledging the mind-mess side of this, it is brutal right now. The extreme excitement I have had for a full track day of instruction this Friday and a vacation to go to the Rally in 2 weeks, has been replaced with just feeling ill.

The car has not been driven hard. The only owner between the fluid change and me drove like he was afraid to even let the revs go to 4k. The correct oil and the wrong oil are both synthetic gear oil of the same weight. I'm with Pete K in that is very hard for me to grasp how that could seriously damage anything in 1k miles of cruising around. So I am very interested in exploring other plausible theories.

I want to go change that fluid right away and see if it helps the sound, but will doing so be "tampering with the evidence" and undermine my case? There is no way the dealer at fault is going to just accept our forum conclusion and send me a check; the best possible scenario is that they even give me a chance to prove it. The dealer is 800 miles away from me. I need to find out whose hands-on assessment of the situation they will accept. Only their own? A dealer local to me? M2K's?

Does anyone think there would be a contact at Ford Corporate that could help me navigate this?

I won't have a chance to do anything until Friday, will keep in touch
 

2112

Blue/white 06'
Mark II Lifetime
Why do they have a core charge if they only sell new and offer no service on the existing transaxles?

As much as I can appreciate Kendal's suggestion to approach the dealer for compensation, I have a very hard time believing that they will not fight this tooth and nail.

How much do you spend in legal fees to collect something in the $13-16,000 range? There is no pain and suffering (in the eyes of the law) so probably not worth it for an attorney to take on a contingency either, tho I will let Sinovac educate me on this if wrong.

It might be different if you just paid them to do it and now have a problem.

PS, I am on your side too, but don't throw good $ after bad.
 

2112

Blue/white 06'
Mark II Lifetime
The friction modifiers are needed for the clutch pack in older style limited slip diffs. The GT differential has a Torsen limited-slip mechanism. No clutch packs.

Not sure of the answer generically, but the GT Transaxle does NOT require the addition of any friction modifiers.

The friction modifier is required in differentials with clutch packs. The vendors will chime in for sure, but I'm not aware of any manual transmissions/transaxles that require it.

10-4 Thanks
 

ChipBeck

GT Owner
Staff member
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Feb 13, 2006
5,769
Scottsdale, Arizona
Gentlemen,

I was an auto dealer for 25 years and I don't want to be a downer here but I don't think there is a snowballs chance in hell that the dealer will have to pay out. Like the car itself the dealer repairs have a defined warranty period in both miles and time. I had that same noise in my transaxle and it was bugging me. Everything worked fine and most passengers didn't even notice it but I did. My '06 GT has 20,000 miles on it and as of 3 months ago a brand new transaxle. Now it's quiet again and I'm $16,000+ poorer. Perhaps somebody used the wrong fluid in my GT sometime in the past. I don't know but even if they did it's too late to collect now. I suggest you replace it and move on. I know it sucks (I really know!) but it is what it is. Drive it at the Rally and change it afterwards. Cheers.

Chip
 
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nota4re

GT Owner
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Feb 15, 2006
4,176
Yeah, my recommendation was to contact the dealership - in a nice and professional way - to see what their position would be. Putting a non-spec oil into an expensive transaxle is no different to me than doing the same thing to an engine. Manufactures have very precise formula specifications for a reason. The real issue is that there's not likely anyone on the planet who could say for certain that the oil caused the problem. If they were to dig in their heels, I agree that collection would be problematic. But if replacing the transaxle becomes a necessity, maybe they'd at least be willing to get one at cost for Beez. I agree with Chip's recommendation to go enjoy yourself at the Rally and deal with what you want to do after you get back.
 

Beez

GT Owner
Mark II Lifetime
Oct 28, 2016
195
South Denver
I had that same noise in my transaxle ....
Chip

Naturally any other details, no matter how small, are of interest to me. For example, how long (miles/time) would you guess you put up with it and did it slowly worsen over time? Was there anything learned along the way about which parts went bad to cause the noise?


I agree with Chip's recommendation to go enjoy yourself at the Rally and deal with what you want to do after you get back.

I would definitely not be driving it anymore until you can diagnose the problem and find out exactly what is going on inside the car.

Hmmm, pretty opposite advice from very knowledgeable people. What if Mark/Kevin could find a part they could source to fix it, before I make it worse and eliminate all options other than buy a whole new unit?

Very hard to imagine being able to enjoy the UT trip listening to and thinking about this damn noise every mile of the whole time.
 

PeteK

GT Owner
Mark II Lifetime
Apr 18, 2014
2,267
Kalama, Free part of WA State
First, check the oil. Any metal or fuzz? How much? If it's only a little really fine fuzz on the drain plug, that is not uncommon in manny trannies and transaxles. Change the oil and keep driving it, keeping an eye on the oil. One other thing to try: While it's making the noise, push forward and backward on the shifter (moderately) and see if the noise changes. Report back here.

It might not be comforting to you, but I've heard gear whine in all kinds of machines from industrial machines to aircraft, and that was just the way they were. Not a sign of a failure. If the whine doesn't get significantly worse, Take NOTA4RE's advice and keep driving it. Consider it mechanical music! :willy
 

ByeEnzo

GT
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Dec 10, 2005
2,283
Fort Worth, TX
Not to derail the thread, but who on our Forum still sells the transaxle gear oil? I had 5 quarts and just changed mine in preparation for my 3000 mile journey to/from R12. Want to stock up for the next TA service.
To the OP...sorry to hear about your problems. Good advice from the tech gurus here.
 

Xcentric

GT Owner
Mark II Lifetime
Jul 9, 2012
5,213
Myakka City, Florida
^^^ https://www.amazon.com/Ford-XT-75W90-QGT-Synthetic-Transaxle-Lubricant/dp/B000NUAXB8

http://www.ebay.com/itm/Motorcraft-xt75w90qgt-Fluid-Transmission-xt75w90qgt-/361564145942

BTW, the XT-4-QGL they put in the OP's transaxle is a manual transmission fluid. You can't use manual transmission fluid in a transaxle.

Regardless, I'd install the correct fluid, drive the car a few thousand miles, and if it was still noisy, buy a new transaxle.

Three years and two owners ago and 800 miles away? No.
 
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MarkH

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
May 19, 2007
528
Katy, Texas
Here is what I found out. I THOUGHT I had a chance of some parts to maybe fix the problem but after speaking with Kevin he said the tranny we have that is getting PPG gears installed is still using those parts that would be needed to fix this one I believe. SO, right now, I don't have the parts, I know I did purchase a used ring and pinion from Northwood for another tranny but I believe that was the last one he had. Parts are obsolete for sure on these things. We do have many spare parts that we have salvaged over the years of Mile racing but I don't have an additional ring and pinion. Right now, it seems you have a couple of options, first off, I would change the fluid and flush the system as much as possible and see if it is any better. If so, then go with that and go enjoy the Rally and then fix afterwards. At the end of the day, I don't see any option except for replacing the tranny via diagnosing over the internet. If you decide to core the tranny, let me know because we are always willing to buy used/broken trannys for the parts that can be used when others break since we know that Ford will not repari. I know this is not good news as far as money goes but I think Chip said it best. Bite the bullet and get it all right and go out and enjoy that beautiful car you have.

Thanks,
Mark