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Broke something...its not pretty...

Messages
66
Likes
5
Location
M
#63
I'm not terribly familiar with the clutch setup on these yet. Is it possible the gear whine is actually a failing throwout bearing? I haven't done a lot of research on the "gear whine" complaints, but that'd be my first thought.

After that I'd say an internal bearing is bad. draining the trans fluid, you could inspect for metal content in the fluid. If it's actually gear or syncro related you'd get a lot of glitter floating in the fluid. Type of metal would tell a story too. If it's aluminum, then likely something in there is contacting the case walls; brass from syncros/bushings, and steel from gear teeth or shaft.

The shift tower could be at fault? If the tower doesn't relax it's grip on the selector hub after you change gears, it could be holding excessive pressure against the hub and syncro. that kind of contact can result in syncro damage. That's why you read in manuals not to rest your hand on the shifter when driving.

All just spitballing here, since I haven't had one apart, nor have I done a lot of research on the issue or units.
 


Messages
159
Likes
21
Location
Stillwater
#64
So if you've got an aftermarket rear motor mount, do you think if this other mount shears that Ford is likely to blame the stiffer rmm and not repair under warranty?
I guess if warranty is affected it's just a cheap bolt after all, just wondering.
 


PhoenixM3

Senior Member
Messages
806
Likes
510
Location
Colorado Springs
#67
Friend of mine just broke this bolt last night as well. He has a boomba RMM. So a rmm wont solve the issue completely...
Calling all vendors! Your upgraded RMMs are identifying another area for an upgrade. Quick - design and market something Gucci for us.....
 


RAAMaudio

5000 Post Club
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5,268
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925
Location
Carson City
#68
When SS broke his he told me what he did to fix it, I went and bought a bolt at my local Ace Hardware, swapped it out, cheap insurance, done!

---------------------

I have asked others to make a drivers side transaxle mount sleeve but nobody has yet so I might do it if somebody will bring me a stock car to mold if off of which is a very simple process. I built a lighter weight cover for the stock mount that takes out the slack, it would only work for those with a rear battery, for others just a sleeve would do the job. I cannot use my mount as modded it, I need a totally stock one to made the mold from.

There are approx .25" on the top and .125" gaps between the hard rubber on the big billet aluminum section bolted to the transaxle and the cover over it which keeps it in place and is the lower battery mount bracket.

Filling the gab with a simple sleeve will take out the slop and not cause undue vibration, etc, I did not notice any at all on my setup.

I made mine before I even had an RMM(the real name is rear engine mount since we have engines and not motors by the way) and never had axle hop, no more added noise, etc....

Rick
 


JPGC

2000 Post Club
Messages
2,011
Likes
214
Location
Middleburg
#69
That is the next step. The unicorn blood showed up yesterday...
Is this the same Motul (multi DCTF) that all of the Motul users are using in the FiST? I see that some are listing the Motul 300v 75w-90 gear oil.......
 


OP
boombots
Messages
295
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42
Location
Charlotte
Thread Starter #70
They use stuff not ford approved. As I'm sorting out a tranny issue I picked the motul that meets ford specs.
 


JPGC

2000 Post Club
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214
Location
Middleburg
#71
They use stuff not ford approved. As I'm sorting out a tranny issue I picked the motul that meets ford specs.
Thanks, just curious...I've been using AMSOIL MTG 75w-90 for the last 10k miles with no issues what so ever. it shifts great with the stuff. I'm getting ready to drain that fill though and filter it at the same time. I may also send a sample off to see if it is causing any abnormal wear. I'm looking to try Motul since everyone is raving about it, lol. I can compare the two this way.
 


Messages
245
Likes
50
Location
NorCal
#72
Thanks, just curious...I've been using AMSOIL MTG 75w-90 for the last 10k miles with no issues what so ever. it shifts great with the stuff. I'm getting ready to drain that fill though and filter it at the same time. I may also send a sample off to see if it is causing any abnormal wear. I'm looking to try Motul since everyone is raving about it, lol. I can compare the two this way.
The Motul 300 is also 75w-90. I'm looking forward to the results if you ever get the oil tested.
 


westcoaST

1000 Post Club
Messages
1,157
Likes
290
Location
Corona
#73
Guys, there is no such thing as a grade 8 metric bolt. Metric bolts have a class associated with them which consists of two numbers separated by a period. The first number is a function (100 x the number) of the ultimate tensile strength (newtons per square mm). 1 N/mm2 = 145.038 psi. The second number is 10 times the nominal ratio of the yield strength to the tensile strength. For example a Class 8.8 bolt has a tensile strength of 800 N/mm2, which is about 116,000 psi and a yield strength of 640 N/mm2, or 92,820 psi.

Grade 8 SAE (150,000 psi tensile strength) is equivalent to a Metric class 10.9. A metric class 8.8 bolt is equivalent to a SAE Grade 5 bolt.

So you should be looking for a Metric class 10.9 fastener, preferably with a rolled thread. Most hardware stores would not carry a bolt of this strength. I would be looking for a shouldered bolt.

Grades and classes only have to do with the strength of a bolt. Hardness can be used to measure strength, but if you change the alloy, hardness can drop, and the bolt can still be a higher strength.

Secondly, if I could take a look at the fracture faces of the broken motor mount bolts, I can tell you if the failure was due to overload or fatigue, or due to a defect in the bolt. Please photograph the fractured bolt head so I xan look at it. There are telltale signs for specific types of failures. If you are going to purchase an aftermarket bolt, you should know the reason why you are replacing the OEM bolt. This will guide your purchase.
 


RAAMaudio

5000 Post Club
Messages
5,268
Likes
925
Location
Carson City
#74
Most Excellent Info!!!

I did install a 10.9 bolt but not sure now where I got it, could of had one here, will take a look when I drop it down on the lift where I can see it.

Perhaps somebody can find the right type and grade of bolt so others know where to get one.

I am considering this just one more upgrade we need to do if we want to play, at least it will not cost much.
 


Sourskittle

4000 Post Club
Messages
4,567
Likes
860
Location
Lakeland
#76
I don't have my bolt anymore. It looked like it was powder cast, lol. It popped the shoulder/head off like a pezz dispenser. It didn't shear the bolt from the side.

I couldn't find a shouldered bolt, I used a washer.
 


westcoaST

1000 Post Club
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1,157
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290
Location
Corona
#77
SS, from your description, there was most likely a defect in the bolt that caused it to overload. These types of bolts, when they contain forming defects, will not yield very much before they snap. If I have time, I'll pull mine, and take it to work to get it penetrant inspected.

I use boltdepot.com or belmetric.com for my fastener purchases.
 


rodmoe

5000 Post Club
Messages
5,810
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580
Location
wausau
#78
SS, from your description, there was most likely a defect in the bolt that caused it to overload. These types of bolts, when they contain forming defects, will not yield very much before they snap. If I have time, I'll pull mine, and take it to work to get it penetrant inspected.

I use boltdepot.com for my fastener purchases.
If you source a bolt part number please post it or PM it to me I would like to get a better fastener too please. But my car is nowhere to be found at the moment .. lol
 


westcoaST

1000 Post Club
Messages
1,157
Likes
290
Location
Corona
#79
No problem Rodmoe. I'm waiting until I have my Mustang back so I can pull that bolt and let the ST sit. Should be in a couple of weeks.
 


Etyrnus

Active member
Messages
542
Likes
84
Location
Winston-Salem
#80
Curious about the thread pitch on these. Would it be worthwhile replacing the ones for the lower mount as well?
 




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