Excess gear whine from transaxle


Beez

GT Owner
Mark II Lifetime
Oct 28, 2016
194
South Denver
It has taken a long 9 months to work through this problem, but it is with great pleasure today that I start some thread updates that have a happy ending:banana

First, another thanks to Chip for telling me to go to the Utah Rally despite the gear whine. I had a memorably wonderful time, and the gear whine was not even one iota worse after adding 1700 miles and a full track day : )

On the topic of what might have caused the ring/pinion gear whine, and might have it been due to a wrong fluid used. Last year when I was still in touch with the TX Ford dealer about the fluid used, I wasn't ready to publicly point out that although the used fluid analysis wasn't a great match with the sample of correct product, it tested much closer to the make-up of the correct fluid, than it did to the wrong fluid that was available to test. Also, the service manager emphasized that the tech that did the work was very experienced with these cars and had serviced countless FGTs, making it difficult for him to believe his tech would not have been fully aware of the unique fluid need. Perhaps he used the right fluid, but data got entered wrong.

Opinions from several people with automotive and engineering expertise as to whether the wrong fluid could have caused the problem ranged from "maybe, who knows" to "almost certainly not." Of course the bottom line is I'll never know for certain, but when I consider that the "wrong fluid" was, like the correct fluid, a 75/90W synthetic gear oil, differing only in possible additives, and in use for only 1000 easy miles, I've settled in the "almost certainly not" camp.

Reading back through the thread today, this remark from Fubar stands out:

......I have seen at least 3 GT transmissions come through my mechanic's shop with pinion gear teeth that are damaged. I have heard all sorts of speculation on the cause but it doesn't change the fact.
My ring and pinion gear teeth came out rough and had abnormal wear. I'm sure all these other transaxles didn't have the wrong fluid in them. Add my experience to the same list as these others - bad ring/pinion of unknown causality.

Full inspection of my transaxle found no other parts bad, and nothing to explain a cause. Seems to me Ricardo simply put out some parts that had QC issues.
 

2112

Blue/white 06'
Mark II Lifetime
Documented data is hard to come by.

I first did it in 2003 or 2004 and haven't blown up an outdrive since doing it.

Anecdotal stories aside............................are well, you know.

http://www.gearsolutions.com/article/detail/5937/cryogenic-treatment--of-gears
 

Beez

GT Owner
Mark II Lifetime
Oct 28, 2016
194
South Denver
In the prior pages you will note that our member B.M.F. offered to see if he could actually repair my transaxle, rather than replace it entirely with a new unit. I could find no one else in the country able to offer such a repair. I very much favored repair over replace, to maintain a numbers-matching car in regards to such a major component. Greatly reduced cost was a nice secondary consideration.

Once I was focused on repair rather than replace, then the whole dealer-that-changed-the-fluid thing became a moot point.

So last Christmas I journeyed to the gray farmlands of rural Minnesota to meet one Dan Schoneck. Checked out his operation, looked him in the eye, shook his hand, and decided Dan was the Man to take this project to the Promised Land. Shipped the car out later on.

And he did it! The car is back home, and back to it's pristine, problem-free, no gear-whine condition. I could not be happier! I believe that in the years ahead many other FGT owners will discover what a valuable member of our community Dan is.:cheers

Brian
 
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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
 

Beez

GT Owner
Mark II Lifetime
Oct 28, 2016
194
South Denver
I have no experience to know what mild vs moderate wear looks like on gears, but it seems to me there is nothing real drastic looking here. I can't feel any change in the surface with a finger or fingernail.

I'm interested in any feedback, but it makes me think that not only was Chip right about not worrying about about driving it with the gear whine, but that I could probably have driven it til I'm 90 years old without any repair. But I couldn't stand listening to it.

I think there is more to see on the pinion than the ring. Looking at the the small end of the pinion teeth, it looks to me like the contact was too far towards the outside of the gears. (bottom pic)
 

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ChipBeck

GT Owner
Staff member
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 13, 2006
5,603
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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FENZO

GT Owner
Mark II Lifetime
Jul 7, 2008
1,516
Lafayette, CO
Whatever it is, I'm glad you got it fixed and can now drive confident something bad isn't about to happen.
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
3,804
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
194
South Denver
Whatever it is, I'm glad you got it fixed and can now drive confident something bad isn't about to happen.
Thanks Steve - Car season is here, we need to cook up a reason to get together : )
 

2112

Blue/white 06'
Mark II Lifetime
At the very least, I would check into having those polished and cryo'd and hang onto them as a spare set....just in case.
 

Beez

GT Owner
Mark II Lifetime
Oct 28, 2016
194
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.
 

Beez

GT Owner
Mark II Lifetime
Oct 28, 2016
194
South Denver
At the very least, I would check into having those polished and cryo'd and hang onto them as a spare set....just in case.
Yep I am good at hanging on to car parts : ) I did have the new set that got installed micropolished.
 

PeteK

GT Owner
Apr 18, 2014
1,301
Kalama, WA
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
 

Art138

GT Owner
Mark II Lifetime
Jan 4, 2011
412
Weston,FL
If they took pics of the damaged pinion gear and ring if would be useful for you to post.
 

ByeEnzo

GT
Mark IV Lifetime
Le Mans 2010 Supporter
Dec 10, 2005
2,087
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.
 

FENZO

GT Owner
Mark II Lifetime
Jul 7, 2008
1,516
Lafayette, CO
Thanks Steve - Car season is here, we need to cook up a reason to get together : )

How about a late lunch (1:00) tomorrow at Twin Peaks at Colorado Mills? Or a late late lunch (3:00) at the Keg? That's roughly midway between us and they have outdoor seating with ample parking (lot in view). I could even do dinner at the Keg, love that place.


Posting here vs PM since all other Denverites are welcome!
 

NorthwoodGT

GT Owner
Jun 12, 2009
1,100
Michigan
another product for moving fluid easily is the hand pump that screws onto the quart bottle that's used for marine out drives and out boards to fill the lower unit. same principal and can be bought for about $8.95. that's all I've ever used.
 

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
479
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