90 Gt T5 Issues

Hi all!!
I've been disconnected for a while and need help with this issue:
I upgraded my T5 WC with a set of Z specs set of gears with carbon synchros. Since day one I had issues shifting gears @ high rpm it feels like the synchros don't slow down the gears and it is hard to disengage. I'm using Mobil 1 synthetic fluid, and I heard somewhere that this fluid is too slippery for the carbon synchros to grab/slow down the gears for proper shifting. Is this truth? Should I use regular Mercon V ATF instead?
Thank you for the help!!!
 
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The first thing to check when you have shifting issues is the clutch adjustment.


Clutch adjustment
Do the clutch adjustment first before considering any other problems. With the stock plastic quadrant and cable, pull up on the clutch pedal until it comes upward toward you. It will make a ratcheting sound as the self adjuster works. To release to tension of the stock quadrant, use a screwdriver to lift the ratchet paw up and out of engagement with the quadrant teeth.

A binding clutch cable will make the clutch very stiff. If the cable is misrouted or has gotten too close to the exhaust, it will definitely bind. The binding common to adjustable cables is often due to misplacement of the adjusting nuts on the fork end of the cable. This will also cause the cable to wear and fray. Both nuts should be on the back side of the fork so that the domed nut faces the fork and the other nut serves as jam or locknut to the domed nut.

Clutch pedal adjustment with aftermarket quadrant and cable: I like to have the clutch completely disengaged and still have about 1.5” travel left before the pedal hits the floor. This means that I have only about 1” of free play at the top before the pedal starts to disengage the clutch. Keep in mind that these figures are all approximate. When properly adjusted, there will not be any slack in the clutch cable. You will have 4-15 lbs preload on the clutch cable.

Adjustable clutch cable tips:
Loosening the cable adjustment nut (throwout bearing arm moves to the rear of the car) moves the disengagement point towards the floor.

Tightening the cable adjustment nut (throwout bearing arm moves to the front of the car) moves the disengagement point towards the top of the pedal.

The quadrant needs to be replaced if you use any type of aftermarket cable or adjuster. My preference is a Ford Racing quadrant, adjustable cable and Steeda firewall adjuster. The adjustable Ford Racing cable is just as good as the stock OEM cable. It allows a greater range of adjustment than a stock cable with a aftermarket quadrant and firewall adjuster. Combined with the Steeda adjuster, it lets you set the initial cable preload and then fine tune the clutch engagement point to your liking without getting under the car.

Using a stock OEM cable, firewall adjuster and a single hook quadrant may result in not having any free pedal travel before the clutch starts to disengage. I found this out the hard way.

See Summit Racing - High Performance Car and Truck Parts l 800-230-3030 for the following parts.

Ford Racing M-7553-B302 - Ford Racing V-8 Mustang Adjustable Clutch Linkage Kits - Overview - SummitRacing.com Cable and quadrant assembly $90

The Ford Racing Adjustable cable is available as a separate part:
Clutch Cable, Adjustable, Ford, Mercury, 5.0L, Kit FMS-M-7553-C302_HE_xl.jpg

[url=http://www.summitracing.com/parts/SDA-555-7021/]Steeda Autosports 555-7021 - Steeda Autosports Firewall Cable Adjusters - Overview - SummitRacing.com
Steeda firewall adjuster. $40

555-7021.jpg


Fix for the quadrant end of the cable popping out of the quadrant when installing a replacement cable courtesy of Grabbin' Asphalt
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Last edited:
jrichker, it is always a pleasure to have your input and suggestions to our problems.
I totally forgot to add my clutch information in my call for help; I have a Spec stage 2+ clutch and a Steeda quadrant as well as Steeda firewall adjuster. Also my pedal travel numbers are very similar to yours.
While waiting for replies I changed the tranny fluid this time using the standard Mercon V fluid and seems to work a little better I will try to validate these results and will double check my clutch cable adjustments.

Thank you a bunch!!!!
 
Hello,
I still having the hard to shift at high RPM, it feels like the blocking rings are not slowing down for the gears to engage. I have been using synthetic Mobil1 ATF fluid since day one after the rebuild.

I heard that this fluid is too slippery and don't grab to slow down the blocking rings, also comments about using different brands of Sinchromesh. I also read that using Mobil 1 synthetic fluid and a bottle (4oz) of friction modifier will work fine.

So, can somebody help me to understand if my problem is caused by using Mobil 1 Synthetic fluid and if using that fluid plus the friction modifier will solve the hard shifting issues. Does any one has been using that fluid mixture with success and if the friction modifier will cause any known damage to either the carbon blocking rings or the bonding epoxy?

Thank you all in advance !!!