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TKO-500 & TKO-600 users: how high in RPM can you shift?

  • Thread starter Thread starter FastGT94
  • Start date Start date Jul 12, 2007
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FastGT94

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Jul 12, 2007
#1
  • Jul 12, 2007
  • #1
I'm currently debating what transmission to replace my old one with.

The only thing leaving me hesitant about the TKO-500 or 600 is the high RPM shift issue.

I understand that Tremec offers improved Shift Lugs that help to allow the trans to engage up to 6500 RPM now, but I haven't heard too many people stating that they shift this high either.

So in short: If you use a TKO-500 or TKO-600, are you experiencing shifting issues (if so what RPM) and if not, what RPM are you shifting at?

My goal is to determine if the shift lugs truly solve the problem that these transmissions seem to be hit or miss on.

Thanks!
 

ShortThrow50

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Oct 22, 2006
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#2
  • Jul 12, 2007
  • #2
My tko600 which is a month old shifts at redline with ease. Maybe you are listening to old stories about the old units.
 

FastGT94

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#3
  • Jul 12, 2007
  • #3
What is your redline? 5800?
 

Modular2v

Founding Member
Jun 30, 2002
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oklahoma
Jul 12, 2007
#4
  • Jul 12, 2007
  • #4
g force here shifting at 6800!
 

Grn92LX

Fidanza Man!
Founding Member
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Jul 12, 2007
#5
  • Jul 12, 2007
  • #5
I've shifted my old tko and my current 3550 in the near 7,000 range, zero issues what so ever. 6,500 is nothing. My old t5z shifted fine in the near 7,000 range as well. You'll need a good clutch too capable of rpm also if youre looking to shift high. 6,500 is nothing though.
 

FastGT94

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#6
  • Jul 12, 2007
  • #6
ShortThrow50 said:
My tko600 which is a month old shifts at redline with ease. Maybe you are listening to old stories about the old units.
Click to expand...

I definitely am hearing the stories about the old units but I want to be sure their "fix" is truly a fix considering they claimed nothing was wrong with the old ones...
 

ShortThrow50

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#7
  • Jul 12, 2007
  • #7
FastGT94 said:
What is your redline? 5800?
Click to expand...

yeah. its somewhere around there.
 

bill302

Active Member
Nov 2, 2005
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alabama,gadsden
Jul 12, 2007
#8
  • Jul 12, 2007
  • #8
i shift my tko 500 at 54-5600 rpms with 429.4 ft lbs of torque with no problems....
 

QUIKSVT

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May 19, 2006
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#9
  • Jul 12, 2007
  • #9
I shift my T5 with 590 lb/ft but that doesn't mean I'm spinning anymore rpm than the next guy...
 

SMOKEDYA

20+ Year Stangneter
Jul 13, 2003
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Jul 12, 2007
#10
  • Jul 12, 2007
  • #10
Not shure i have a 3550 and it shifts like crap into 2nd at high RPMS. I'm taking it to a guy that is a tremac rep at the end of this month and he will go threw it for me. He is doing a 3550 right now for a guy that is having a similair problem as i am. I have heard that D&D makes a special shifting gear system for the pro5.0 guy's? peace


john
 

EMW150

Founding Member
May 22, 2000
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Jul 13, 2007
#11
  • Jul 13, 2007
  • #11
Powershifting any synchronized trans much over 7,000 is hit or miss. I've dealt with this for years. The fine teeth on the synchronizer will do their job to align before engaging which blocks the shift. It really doesn't have much to do with the shift lugs. That's why I had my TKO faceplated. 7,800 rpms powershifts are smooth and effortless but really clunky on the street.
 

millhouse

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May 14, 2002
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Jul 13, 2007
#12
  • Jul 13, 2007
  • #12
SMOKEDYA said:
Not shure i have a 3550 and it shifts like crap into 2nd at high RPMS. I'm taking it to a guy that is a tremac rep at the end of this month and he will go threw it for me. He is doing a 3550 right now for a guy that is having a similair problem as i am. I have heard that D&D makes a special shifting gear system for the pro5.0 guy's? peace


john
Click to expand...

I can shift my 3550 up to 6500 rpm without any trouble.
 

EMW150

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Jul 13, 2007
#13
  • Jul 13, 2007
  • #13
SMOKEDYA said:
Not shure i have a 3550 and it shifts like crap into 2nd at high RPMS. I'm taking it to a guy that is a tremac rep at the end of this month and he will go threw it for me. He is doing a 3550 right now for a guy that is having a similair problem as i am. I have heard that D&D makes a special shifting gear system for the pro5.0 guy's? peace


john
Click to expand...

Most likely you're looking at a clutch problem at that rpm. There are alot of clutches out there that have poor disengagement at higher rpms. Spec cluches are very good at high rpm release. The Centerforces, Zoom, etc seem to struggle for the most part in that department.
 

Auto Reverse

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Jul 22, 2003
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Buffalo, NY
Jul 13, 2007
#14
  • Jul 13, 2007
  • #14
I shifted my brand new TKO600 with no problems at 6500+ RPM's. Excellent transmission!
 

Italian-LX

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Anniston, AL
Jul 13, 2007
#15
  • Jul 13, 2007
  • #15
I bought my TKO500 in Spring 2006 and it has never shifted well at high RPM's. Third gear is near impossible to hit in a racing situation. Now that I have learned to granny-shift 3rd, I can usually hit it, but when I try to shift quickly (not power shifting) I porobably hit 3rd 20% of the time. The rest of the time, it feel like it went into gear, but when you let out on the clutch, the engine just free-revs. Also, starting this past winter, it refuses to down shift from 4th to 3rd. In order to do so, I have to pull it over into second and then up into 3rd.

Since I bought it, I it has been behind two different motors (and H/C/I 302 and now a 418W) and I've had three different clutches on it (one used Center Force D/F and two brand new SPEC Stage 3's). There was no difference betwen any of the changes -- the TKO always shifted like crap in the high RPM ranges.


This is the biggest piece of crap tranny I have ever owned. Sure, it may be able to handle more than my old T-5, but what good is a tranny that won't break if it slows you down.

I've talked to more than two people who have personally had the same issue along with many posts on various internet forums. However, I have also heard people praising the shifting capabilities of their TKO's. It appears to be hit or miss with these transmission which doesn't say much about Tremec's quality control.

I'll probably be pulling the transmission this fall and rebuild it myself... maybe look into upgrading some of the internals to help with the shifting. I'm not ready to give up on it yet, but it sure is testing my limits.
 

FastGT94

Member
Nov 20, 2003
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Jul 13, 2007
#16
  • Jul 13, 2007
  • #16
Thank you for your reply. It is the hit or miss of the older ones that worries me.

However, there seems to be a silver lining from what I've read.

Check the build date on your trans, It seems Tremec offers improved shift lugs that should solve the problem. In fact I read of a few instances of people who installed this improvement to their TKO 600's and the trans was then able to hit 3rd no problem. In my research I have found this out as well as the fact that the latest build of the TKO600 has the improvement that supposedly fixes this problem from the factory.

Unfortunately, yours is old enough where it wouldn't have the improved parts.
 

EMW150

Founding Member
May 22, 2000
2,020
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Jul 13, 2007
#17
  • Jul 13, 2007
  • #17
Italian-LX said:
I bought my TKO500 in Spring 2006 and it has never shifted well at high RPM's. Third gear is near impossible to hit in a racing situation. Now that I have learned to granny-shift 3rd, I can usually hit it, but when I try to shift quickly (not power shifting) I porobably hit 3rd 20% of the time. The rest of the time, it feel like it went into gear, but when you let out on the clutch, the engine just free-revs. Also, starting this past winter, it refuses to down shift from 4th to 3rd. In order to do so, I have to pull it over into second and then up into 3rd.

Since I bought it, I it has been behind two different motors (and H/C/I 302 and now a 418W) and I've had three different clutches on it (one used Center Force D/F and two brand new SPEC Stage 3's). There was no difference betwen any of the changes -- the TKO always shifted like crap in the high RPM ranges.


This is the biggest piece of crap tranny I have ever owned. Sure, it may be able to handle more than my old T-5, but what good is a tranny that won't break if it slows you down.

I've talked to more than two people who have personally had the same issue along with many posts on various internet forums. However, I have also heard people praising the shifting capabilities of their TKO's. It appears to be hit or miss with these transmission which doesn't say much about Tremec's quality control.

I'll probably be pulling the transmission this fall and rebuild it myself... maybe look into upgrading some of the internals to help with the shifting. I'm not ready to give up on it yet, but it sure is testing my limits.
Click to expand...

The other thing you have to watch is the clutch adjustment. Not just cable adjustment but the clutch fork pivot. I have my fork pivot shimmed out to put the clutch fork as far rearward as possible in the window. This can help dramatically if the clutch isn't releasing fully because it gives you alot more travel. Just something else for you guys to try.
 

EMW150

Founding Member
May 22, 2000
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Jul 13, 2007
#18
  • Jul 13, 2007
  • #18
Italian LX just curious which shifter are you're using.
 

Italian-LX

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Dec 9, 2002
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Jul 13, 2007
#19
  • Jul 13, 2007
  • #19
EMW150 said:
The other thing you have to watch is the clutch adjustment. Not just cable adjustment but the clutch fork pivot. I have my fork pivot shimmed out to put the clutch fork as far forward as possible in the window. This can help dramatically if the clutch isn't releasing fully because it gives you alot more travel. Just something else for you guys to try.
Click to expand...
I've already messed with different clutch cable adjustments, but I haven't thought about shimming the pivot out. I did, however replace my pivot ball and clutch fork just before swapping to the TKO, so I know those items are up to par.

I'm pretty comfortable that the clutch is fully releasing. Heck, two months ago, I put a in brand new aluminum flywheel and stage 3 clutch.
 

Italian-LX

Member
Dec 9, 2002
970
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Jul 13, 2007
#20
  • Jul 13, 2007
  • #20
EMW150 said:
Italian LX just curious which shifter are you're using.
Click to expand...
I used the stock TKO shifter with a tri-ax handle for a few thousand miles and then switched over to the Tri-ax shifter. The Tri-ax felt a bit more solid, but it didn't help with the crappy 2-3 shift.

I ran a Tri-ax for years on my T-5 and loved it.... and NEVER missed 3rd gear.
 
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