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Topic: Tremec TKO Will Not Go Into Gear (Read 2093 times) previous topic - next topic

Tremec TKO Will Not Go Into Gear

I took the Bird out for about a ten mile cruise and from the beginning the trans was super notchy going into any gear.  Even for a Tremec TKO is was overly burdensome to get into gear.  As the drive progressed it got to the point where I could not get it into gear at all.  I called the house and had my father bring a jack and some tools to adjust the clutch cable as the car had zero clutch.  After getting it up in the air I saw the nut on the cable backed almost all the way off and there was no jam nut.  This was all my fault as I adjusted the cable but did not install the jam nut so I readjusted the cable.  With only four miles to get back to the house I figured it would make it that far with what I was able to do on the side of the road and I could get it back up on the lift to install the jam nut.  After a little more inspection I saw some wires that appeared to be broken clutch cable wires so I hoped that it would make it back to the shop where I had a spare clutch cable.  Needless to say I got it back to the shop and just barely as I could only get it into 4th as again I had little to zero clutch.  I will say that slipping the clutch at 4,500 rpm and leaving off two red lights in 4th was only possible with the 351W and the 4.10 gears.  I got it up on the lift and found out what was going on, the clutch cable was toast.  The wires that I saw were not the cable strands but the wires under the clutch cable sheathing.  It was hard to determine what these wires were on the side of the road as I had previously wrapped the lower portion of the cable in header wrap.  When I got it back to the house and and pulled the cable it was very apparent what was going on.  Here is a picture of the old cable next to the new one:



I also purchased a firewall adjuster as I could never get one on the car with the stock T-Bird booster.  With the SN95 booster it fits like one would expect:



I went ahead and pulled the X-Pipe, the collectors off the headers, and driver shaft to remove the transmission as it had a fluid leak.  I suspected it was the seal between the tail housing and the case as that is where it was dripping.  We pulled the two inspection plates on the top of the transmission and immediately found the leak.  The forward inspection plate lost its seal at some point and the fluid was running on top of the trans and found its way to the tail housing to case joint and ran down the tranny so that is an easy fix.  We looked over the internals and about the only issue we found was the 1-2 & 3-4 shift fork pads were boarder line on needing replacement so I ordered new ones as well as some new GM synchromesh fluid.

We are going to have to pull the tail housing off the tranny to change the shifter fork pads so I decided to look around to see if anyone made a 6 tooth speedo drive gear for the output shaft of a Tremec TKO.  With the 4.10 gears and the stock 7 tooth drive gear in the TKO I am having to run a 23 tooth driven gear which is not optimal.  I found one thread on the Corral where a guy had to modify a T-5 speedo drive gear to fit the larger diameter TKO output shaft which I thought to be sketchy at best.  The T-5 speedo drive gear slides onto a splined section of the T-5 output shaft.  This guy used a Dremel to make the ID of the T-5 speedo drive gear larger to fit the bigger output shaft of the TKO.  The TKO has a 1-3/8" diameter output shaft and the ID of the original 7 tooth speedo drive gear is smooth.  I did some serious searching on the net and I think that Tremec is simply using the speedo drive gear design from the old Ford Toploaders as they have 1-3/8" output shafts and the speedo drive gears have smooth ID's.  I am not 100% sure but I went ahead and purchased a new 6 tooth drive gear for the Toploader and a 19 tooth driven gear for the VSS.  I will know more about this in the next couple of days and will post up with some pictures.

Hopefully all of this will solve my shifting issues and I can get back to the custom instrument cluster I have been working on.  When that it finished I will start a thread on that as the 83-84 cars are not as friendly so this mod as the 85-88 cars due to the really narrow instrument cluster.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang coupe that beat your mom's LTD

Tremec TKO Will Not Go Into Gear

Reply #1
I tore the TKO down and everything looked good so I replaced the shift fork pads on 1-2 & 3-4.  The pads on the 5-R fork looked really good but that is to be expected due to the less frequent use of 5th and Reverse compared to 1st, 2nd, 3rd, and 4th gears.  After hunting for the shift rail guide o-rings (you need nine of them) I was able to locate them locally and they are a #19 industrial type Buna 70 o-ring.

As for the Toploader speedo drive gear, my hunch was correct with the exception of the worm gear tooth profile was opposite of the TKO worm gear.  What this means is that if you were to use the Toploader speedo drive gear with an T-5 speedo driven gear it would turn the speedo the wrong way.  To get around this I am going to use a Toploader speedo driven gear which is cut the opposite direction of the T-5 speedo driven gear so the speedo will turn the correct way.

Here is a shot of the transmission torn down with the pink Toploader 6 tooth driver gear installed:



I wrapped the new clutch cable with black header heat wrap and used stainless steel ties to keep it from unraveling and it looks pretty good and a lot better job than the last time I did this.  I should get the isolator from Maximum Motorsports tomorrow which goes into the bell housing where the speedo cable it inserted.  This is supposed to keep the heat from the transmission from transferring to the clutch cable.  Under normal conditions I don't think this is a huge deal but for $8 it is some added insurance.

I'll take some pictures tomorrow and update the thread then.  Hopefully if all goes well I can take it for a spin tomorrow afternoon.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang coupe that beat your mom's LTD

Tremec TKO Will Not Go Into Gear

Reply #2
Darren, did you have the original booster in the car with the current engine, or was the booster swapped before the 351w? I did read your thread sometime back, but I just don't recall when you did your booster.

I'm thinking of putting a 351w into my '84, and wondered if the booster swap was necessary simply because of the width of the 351 at the valve covers, compared to the 302. Likely I'll swap anyhow, if only to use the firewall adjuster, but wanted your first hand info.


Looking forward to reading your next update on your cable fix, too. :)
'84 and '87 Mustangs
'98 Explorer 5.0
'06 Lexus
'06 Explorer EB 4.6

Tremec TKO Will Not Go Into Gear

Reply #3
The booster swap was done when I converted the car over to SN95 spindles and Cobra brakes at all four corners. If memory serves me correctly I could get the firewall adjuster installed with the stock booster but the booster shrouded it so much adjusting it was very difficult and it limited how much a person could adjust it. I would also say that it's not necessary to get a 351W in the car but would be a good idea.

If I had to do it over again I would have used a 1993 Cobra booster instead of the 1995 booster. The Cobra booster has the Fox bolting pattern with regards to attaching to the firewall so it makes the installation a snap.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang coupe that beat your mom's LTD

Tremec TKO Will Not Go Into Gear

Reply #4
Something told me to check the end play of the input shaft on the transmission so that took a bit on Thursday to get the dial indicator set up but I ended up with this and it was a very solid mount and accurate:



When we finally got it set up there was a total of 0.013" of end play and Tremec requires 0.000" to 0.004". After some discussion I decided to order shims and get it as close to 0.002" as I could. Finding someone that had the shim packs was one thing but finding someone that was willing to hustle and get them shipped so I could have them by Friday was another. Needless to say I was able to find my way to the Tremec guru in Ft. Worth, TX and he made it happen.

Got the end play of the input shaft to 0.002" and called it good as this was with the bearing retainer bolted to it dry. I figure with the sealant it probably loosen it up to 0.0025". Finally got everything reinstalled today and after an hour or so of battling the finicky RAM clutch I finally got the clutch cable adjusted to my liking. Needless to say the TKO shifts better than I remember when it was new and I was able to road test the car. I was able to remove the top layer of old rubber on the 275/40/17's pretty easily with the 351 and get to some decent rubber. I am probably going to try and get some Nitto drag radials as these low profile Yokohamas cannot come close to handling the motor.

I messed up and thought I took a couple of pictures of the clutch cable with the header wrap out of the car but evidently I did not.  I took a couple of it installed so you can get an idea:





Anyhow, just wanted to update the thread with what all finally fixed the problem.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang coupe that beat your mom's LTD

Tremec TKO Will Not Go Into Gear

Reply #5
Nice.  Do you know if your tremec has the 2.87 or the 3.27 first gear ratio and  how do you like it with the 4.10s?

Tremec TKO Will Not Go Into Gear

Reply #6
It has the 3.27 first gear ratio and its fine with the 4.10's.  If you get into the throttle in first you had better be ready to grab second and quick like.  For me its dump the clutch in first for a count of about two and grab second.  It was a little better with the 3.73's but my engine builder said that with the cam that is in this motor the 4.10's were going to be needed.  So far I do not doubt anything he as told me.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang coupe that beat your mom's LTD

Tremec TKO Will Not Go Into Gear

Reply #7
Man, we know you are glad to have some seat time in the bird.  Makes me want to get to work on mine as soon as I can.