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  • Fox 5.0 Mustang Tech

Grinds Into Gear On Hard Shifting

  • Thread starter Thread starter foxbodymike87
  • Start date Start date May 15, 2012
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foxbodymike87

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Jul 12, 2011
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#1
  • May 15, 2012
  • #1
Ok, i know i dont have a fox anymore but the ppl in this section give the quickest response..so on my 97 cobra with a stage 2 clutch it shifts perfectly just cruising..but when u push the clutch in all the way and slam it into the next gear it grinds badly...anyone know what can cause this?
 

boostfrk

10 Year Member
Aug 30, 2011
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Colorado
May 15, 2012
#2
  • May 15, 2012
  • #2
Sounds like synchros. I believe, when you are shifting normally (ie: slowly) you're giving the synchro enough time to align for your gear change. When you slam it from gear to gear (ie: really fast) the synchros don't have enough time to align, and hence the grind.
 

srtthis

the guy doing it does every local racers rear end
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#3
  • May 15, 2012
  • #3
could also be your timing...
 

tannerc91gt

This last 25% is foreign territory at this point
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#4
  • May 15, 2012
  • #4
most likely cause is worn transmission syncros. That or you're an awful driver, but who am i to judge
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
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May 15, 2012
#5
  • May 15, 2012
  • #5
My 3550 does this every now and then when i'm really giving it hell. It's always into 3rd though so i just assumed it's getting due for a rebuild.
 

NIKwoaC

中國製造
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#6
  • May 15, 2012
  • #6
Synchros, shifting technique, clutch adjustment, fluid type. Try adjusting your clutch so it engages a little further from the floor and put a high performance AT fluid in it like B&M Trick Shift. If it still grinds then your driving either really sucks or the synchros are shot.
 

foxbodymike87

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Jul 12, 2011
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May 15, 2012
#7
  • May 15, 2012
  • #7
i know its not my driving because i said i press the clutch in fully and then put it into gear.. im not just bangin gears..and clutch releases at the top of the pedal.
 

foxbodymike87

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#8
  • May 15, 2012
  • #8
also, tranny was just rebuilt.
 

stykthyn

I want to measure mine. It doesn't look that tall.
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#9
  • May 15, 2012
  • #9
Drain the fluid and replace with redline synthetic. Worked wonders for the 5spd in me jeep.
 

srtthis

the guy doing it does every local racers rear end
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#10
  • May 15, 2012
  • #10
foxbodymike87 said:
i know its not my driving because i said i press the clutch in fully and then put it into gear.. im not just bangin gears..and clutch releases at the top of the pedal.
Click to expand...
That doesn't mean anything... Might be off clutch a hair sooner then it's in gear or not actually getting the clutch at all... As nic said try adjusting cable and going from there. Another trick is add friction modifier to the trans
 

foxbodymike87

Active Member
Jul 12, 2011
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May 15, 2012
#11
  • May 15, 2012
  • #11
still dont think you understand..i put the clutch in for 5-6 seconds and in the time period i rip into the next gear to make sure that im on the clutch..and im gunna put it some diff fluid.
 

srtthis

the guy doing it does every local racers rear end
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May 16, 2012
#12
  • May 16, 2012
  • #12
so if you push the clutch in to the floor and just rip the shifter back it grinds?
 

SVT32VDOHC

waiting for the next hack atta
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May 16, 2012
#13
  • May 16, 2012
  • #13
You have a synchro problem. Grinding gears is all about the synchros. Fluid won't fix your problem.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
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May 16, 2012
#14
  • May 16, 2012
  • #14
NIKwoaC said:
Synchros, shifting technique, clutch adjustment, fluid type. Try adjusting your clutch so it engages a little further from the floor and put a high performance AT fluid in it like B&M Trick Shift. If it still grinds then your driving either really sucks or the synchros are shot.
Click to expand...

The highlighted portion would be my first guess. Put a turn or two on the FW adjuster.
 

Gearbanger 101

Straight Outta Locash
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May 16, 2012
#15
  • May 16, 2012
  • #15
SVT32VDOHC said:
You have a synchro problem. Grinding gears is all about the synchros. Fluid won't fix your problem.
Click to expand...
I disagree. A good synthetic ATF fluid can make grinding between gears disappear if the synchro's aren't too far gone. Been there, done that. Ran Mobil 1 synthetic ATF in my last Mustang and the grinding went away.
 

srtthis

the guy doing it does every local racers rear end
15 Year Member
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May 16, 2012
#16
  • May 16, 2012
  • #16
SVT32VDOHC said:
You have a synchro problem. Grinding gears is all about the synchros. Fluid won't fix your problem.
Click to expand...
fix it? no... mask it... yes
 

SVT32VDOHC

waiting for the next hack atta
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May 16, 2012
#17
  • May 16, 2012
  • #17
You got lucky then. Everytime I tried that trick I had no luck. Just fix it so it's right and you don't have to worry about it in the future. You don't wanna get stuck in gear and have to leave your car somewhere.
 
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1990Coupe

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#18
  • May 16, 2012
  • #18
I've never seen synthetic ATF clear up grinding issues.. sorry that doesn't plausible one bit.
 

Gearbanger 101

Straight Outta Locash
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#19
  • May 16, 2012
  • #19
1990Coupe said:
I've never seen synthetic ATF clear up grinding issues.. sorry that doesn't plausible one bit.
Click to expand...
Lol....and that's the way it is, because I said so!!!

It doesn't matter whether you've seen it or not, it does work in many cases. The synthetic fluid has better low temperature fluidity and works its way around the parts more thoroughly. It flow characteristics remain more consistent as temperature changes.....especially during cold starts where standard ATF needs to warm up a little to perform properly. It also dissipates and resists breakdown with heat better than standard ATF and most importantly, doesn't foam like standard ATF.

If the damage, or wear is excessive, then no....no type of fluid is going to cure the problem, but it may very extend its lifespan until a more convenient time to rebuild the trans presents itself. It may and in many cases hasit extend the life of the transmission by months or years. How many of us have driven for extended periods of time with whiney T5's and said to ourselves...."I'm gonna get this looked at soon", only to never get around to it? Synthetic trans fluid works and it's worth a shot if it saves you from having to do a rebuild for another year or two.

Another popular fluid for T5 guys is GM Synchromesh. Good stuff.
 

NIKwoaC

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May 17, 2012
#20
  • May 17, 2012
  • #20
I've been through 3 T5s in my car and experimented with a lot of different fluids and this is how I see it:

Worn synchros with junk fluid- bad
Worn synchros with good fluid- ok
Good synchros with junk fluid- good
Good synchros with good fluid- great

The way I see it is that the synchros need to work with the fluid to provide good shifts, so both parties are somewhat responsible. Over my travels, I've found the Trick Shift or Hot Shift SEEMS to have a noticable increase in shift smoothness, the synthetic stuff I did not notice a huge difference. I ran Redline MTF in one of my old T5s years ago and would like to give it a shot in my new trans, but that stuff is not exactly off-the-shelf.
 
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