Tremec T170 Transmission Troubles (this issue may be a puzzle)

[shew01]

I purchased my 1931 Victoria (my first Model A) about a year ago, and, over the weekend, the transmission (or the clutch or maybe something else) developed a new noise that sounds/feels like a piece of metal flying around in the gearbox or the bell housing. (The sound reminds me of a marble flying around in a clothes dryer, ricocheting off something.) The noise is NOT a steady grind or drone. I can often feel the random noise in the clutch pedal. Sometimes, I can feel the noise in the stick shift as I pass through neutral. This occurred while I had the car out of town. I drove it home about 150 miles (mostly around 40-45 MPH), and the noise came and went along the way. I don't notice any difference in power or acceleration.

The previous owner converted the transmission to a 1984 Ford Bronco top loaded, manual, Tremec T170 synchronized transmission with overdrive and a Model A (not AA) bell housing. The torque tube and the rear radius rods have been shortened to accommodate the replacement transmission. I don't know if the drive shaft was shortened or not, but I presume it was since the torque tube was shortened. Please see http://www.fordgarage.com/pages/TremecT170FT.htm for more information about the transmission, if you like.

I usually notice the noise in third or fourth gear. It's rare to hear the noise in first or second. When the noise occurs, I can usually press in the clutch, and the noise will at least change and usually go away. Once I stop the car, the noise usually will be silent for quite some time. I may drive 15-20 miles without hearing the noise at all.

I've heard that a number of things can "sound" like a transmission issue, even a differential. I know very little about manual transmissions. I've never worked on one, except to adjust the clutch.

So far, this is what I have done.

1. Removed the floor board

2. Removed the filler plug from the T170 transmission

3. Drained the T170 transmission (by using a tool to suck the fluid out through the filler hole because there is no drain plug in this particular transmission--I didn't see any metal shavings in the fluid, I did see a bunch of little air bubbles in the fluid, but I assume that is normal)

4. Removed the inspection plate from the bell housing (I didn't see anything loose while looking through the hole in the bell housing)

5. Used a magnetic tool to see if I could fish any metal chunks out of the transmission through the filler hole (I did not find any loose metal)

6. Used the magnetic tool to see if I could fish any metal chunks out of the bell housing (no loose metal was found)

7. Used a borescope (https://en.wikipedia.org/wiki/Borescope) to peer into the filler hole and the bell housing--I didn't see broken gear teeth or loose parts

What suggestions do you have?

[rotorwrench]

The T-170 RTS is kind of a unique design transmission due to the placement of the overdrive gear on the mainshaft in the normal 3rd gear position with the actual 3rd gear being where the 4th gear would have been in a 4-speed application plus the rocker shift fork mechanism that allows the unit to be shifted from 3rd to OD in that configuration. Other than this overdrive modification, the unit is still a lot like the 4-speed transmission that is was designed from. It has a 1st/2nd syncho set with the reverse gear as the outer hub portion and a 3rd/OD gear synchro set. When you shift to 3rd gear the rocker fork mechanism reverses the movement to push third gear aft then the rocker moves the other way to push the synchro forward to engage the OD gear. This it the only way it would all fit in there and still work as a 3-speed with OD.

If you have what sounds like something bouncing around in there then that certainly could be what is going on. If that's the case, it could eventually go through an engaged gear set. The results would be catastrophic. The top will come off of these units much like any other 4-speeds so a person could take a look in there. I'm not sure who all does the conversions anymore for these. The guys that do this stuff likely know more about them than anyone else and they tend to hoard parts. They would be the ones to call. Parts are getting harder to source for them so a person should make an effort to try and preserve what they have.

There is also a possibility that the U-joint might be loose in the housing. I don't know how they set the U-joint up in these but the conversion guys should. There used to be a few guys that frequented the Ford Barn that played with these things so hopefully one of them will take note. Some have also be used in the V8 cars as well.

[AL in NY]

I would pull the starter and see if anything is broken on the bendix shaft. With the heavy oil in the transmission, I don't think the problem is in there. After removing the starting and the bendix looks good, I'd use a magnetic probe and search around the bottom of the bell housing for any loose parts.

[hardtimes]

Does this setup have throwout bearing, with a return spring ?

Maybe spring came out of position/lose.

[MAG]

shew01 I sent you a pm.

[shew01]

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Originally Posted by MAG

shew01 I sent you a pm.

Thank you.


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[MALAK]

Could be clutch hub spring, see pic, or broken Bendix bolts. This just happened to my A a couple months back. The springs pictured are from the hub of the disk. It made a noise similar to what you described except ALL the springs came out and the car would no longer move due to the clutch being permanently disengaged. I could start and run the car and occasionally hear something (1 of the springs) bounce around in the bell housing.

Since yours has had a trans conversion I suppose the broken Bendix bolt is less likely depending on whether, or not, a Bendix has broken since the conversion.

This same car had the engine lock-up due to a leftover broken Bendix bolt and there are many stories of the same (or noises) happening to other people.

Tom

[shew01]

I plan to take the tower off the transmission when I get a chance. I hadn’t thought about starter parts flying around. That’s a good idea too.


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[shew01]

Tom,

If I remove the starter to take a look, does the starter reattach easily, or do you typically have to “fight” to get it back into the car?


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[JRN1967]

Originally Posted by shew01

I plan to take the tower off the transmission when I get a chance. I hadn’t thought about starter parts flying around. That’s a good idea too.


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shew, if you take the tower off for inspection, you will need to put the tower in second gear before you can reinstall it. The reverse idler gear needs to be towards the rear.

[kenparker]

To add to JRN's note. To get the top/tower OFF the shifter must be in second gear - and to reinstall the top/tower it again must be in second gear.
I doo=bt the problem is inside the gearbox. If it were the rattling around part/piece would have gotten into a gear and broken a toothe by now.

[shew01]

I think I found part of the puzzle.









Am I missing a couple of teeth in the straight cut gear in picture five?



I’m pretty sure this should not be loose in the transmission case. I have no idea where it came from. I was able to fish it out of the case with a magnet. Would something this small make a lot of noise? I’m wondering if anything else is loose in the car, but wasn’t able to find anything else.




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[shew01]

By the way, in case someone else finds this thread useful later, to remove the tower, I:

- Put the shifter in second gear, per PM and previous post (it would have been wise to wrap the end of the shifter with tape to avoid potential scratches)

- Removed the 6 bolts on the bottom of the tower plate

- Wiggled the tower assembly loose and to the passenger side of the car to get it free from the transmission case—be careful—this is awkward, and it would be easy to scratch up the car with the end of the shifter—fortunately, I didn’t scratch anything

I’m guessing that if I move the shifter in the assembly or manage to move the gears, the tower will be more difficult to reinstall.

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[aermotor]

It appears to me that you are looking at a complete overhaul. A lot of damaged and/or missing teeth - it will not get better, only worse and more expensive if used in this condition.

John

[rotorwrench]

Photos of gears can be deceiving so I can't tell what all was affected or how badly. I looks like there are some dents or gashes in the tips of some of the teeth but it's hard to tell from the photos. The piece appears to be a washer or shim. It's also possible that it may be a retaining ring for the rocker but I can't tell. From the patterns of the paper towel, it doesn't appear to be very large either but it doesn't take much to beat stuff up. It would be interesting to find out where that piece came from. The synchros and the forks show some wear but I can't tell if there is any damage.

You will need to find one of the guys that modifies these for early Ford applications to be able to get gear parts unless you purchase a good used unit and trade out parts. Ford doesn't stock them anymore and I don't know of any aftermarket manufacturers to date. You can get gaskets and seals but hard parts are another thing.

[shew01]

Originally Posted by rotorwrench

The piece appears to be a washer or shim. It's also possible that it may be a retaining ring for the rocker but I can't tell. From the patterns of the paper towel, it doesn't appear to be very large either but it doesn't take much to beat stuff up. It would be interesting to find out where that piece came from. The synchros and the forks show some wear but I can't tell if there is any damage.

The metal fragment is about the size of a dime.

When the car is cold, it's tough to shift into second until the engine (and transmission) warm up.

[kenparker]

Shwe, the "missing teeth in picture five" are NOT missing teeth. That is th way the way they are made. A small "rocker " rocks in that space as you shift between the two gears. Syncros and forks and shifters show some minor wear but not enough to effect anything. Nothing out of the ordinary for a 35 year old trann.


As for the small half circle whatever - got me bumfuzzled.

[shew01]

Originally Posted by kenparker

Shwe, the "missing teeth in picture five" are NOT missing teeth. That is th way the way they are made. A small "rocker " rocks in that space as you shift between the two gears. Syncros and forks and shifters show some minor wear but not enough to effect anything. Nothing out of the ordinary for a 35 year old trann.


As for the small half circle whatever - got me bumfuzzled.

You’ve worked with these transmissions a lot, if I recall correctly. If it was yours, would you rebuild it? Or, put it together to see if the noise goes away? Or, maybe something else that I’m not thinking of?


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[rotorwrench]

I'm putting this link on so you can see post #35. Gary in Ft Worth is listed as a person that did these conversion kits utilizing the standard model A clutch housing. It's an old link but he may still be around. The supply of T170 parts and support is slowly depleting but they still show up in salvage yards and on the web sales sites on occasion.
https://fordbarn.com/forum/showthrea...t=43981&page=2

Some folks go the Mitchell route these days even though the original designer of the synchronized transmissions and overdrives has passed. His son took up the business and still manufactures the units as far as I know. It's too bad that no one has taken up the T170 cause. It's not a bad set up although it's not a real heavy duty unit. They were made by Tremec at a factory down in Mexico.

[shew01]

Originally Posted by rotorwrench

I'm putting this link on so you can see post #35. Gary in Ft Worth is listed as a person that did these conversion kits utilizing the standard model A clutch housing. It's an old link but he may still be around. The supply of T170 parts and support is slowly depleting but they still show up in salvage yards and on the web sales sites on occasion.
https://fordbarn.com/forum/showthrea...t=43981&page=2

Some folks go the Mitchell route these days even though the original designer of the synchronized transmissions and overdrives has passed. His son took up the business and still manufactures the units as far as I know. It's too bad that no one has taken up the T170 cause. It's not a bad set up although it's not a real heavy duty unit. They were made by Tremec at a factory down in Mexico.

Thanks for your help. I’ll check out the thread.


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[kenparker]

I ahve built and rebuilt a bunch of them. Since yours has a standard Model A bellhousing I know it is not one of mine. I still do maintenance work and rebuild some of the parts on the inside. I am completely out of useable gears, but still have syncro rings ans bearings - new and good used.


Gary Bernard is still in the business. You can probably find him thru the Ft Worth Model A club.



If you need call me 903 952 7615.

[MALAK]

I've currently got 2 of these transmission on the bench, being built for Model A's. Refer to pics --- there is only 1 washer even close to the size of the one pictured. It's an "E" clip for the Reverse Rocker. The reverse rocker is located in the top of the trans and provides the spring pressure, you must overcome, to put it in reverse. All the other washers are either, large, strong spring clips for the bearings or are captive on their shafts, so unlikely it's any of them. Or possibly at some point the cover was off and a bolt washer was accidentally dropped in there. There is a large, weak, magnet at the bottom of the trans. Looking from the bottom it's in the bulge near the front of the trans and held in by a one-way spring clip.

For those that said the gears look like they have dents or chips, they look perfectly normal to me. Look at the gears in my trans. They ALL have machine makes that look like chips but they are machined on every tooth, all the way around. They all have them. I don't know why but they do.

Without giving away any details this trans is the "Goldilocks Ratio" that was said could not be built. I'm working on writing-up the details of how I accomplished this but I've built 2 of these with the 3.09 first and 27.0% O.D.

Tom

[JRN1967]

Originally Posted by MALAK

Without giving away any details this trans is the "Goldilocks Ratio" that was said could not be built. I'm working on writing-up the details of how I accomplished this but I've built 2 of these with the 3.09 first and 27.0% O.D.

Tom

Tom, How soon can we expect this write up?

John

[Alaska Mike]

Just talked to Gary Bernard yesterday, and yes he is still doing these transmissions. I just about have mine in. Gary does a great job on these. Only three modifications so far, brake cross shaft, and shortened torque tube and shortened radius rods. Gary did the torque tube and brake cross shaft. First Class guy! He has been very helpful!

[MALAK]

Originally Posted by JRN1967

Tom, How soon can we expect this write up?



John

Probably within a month or two. I literally just started documenting the process. Got a lot of other things going on that hinder my attention to projects like this.

Tom

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[rotorwrench]

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I'd forgotten about the tower shifting mechanism. From the parts break down there appears to be two of those clips on the reverse rocker. The retainer rings are as follows: are P/N 97513, a 5/16" retaining ring for the OD/3rd rocker and the two P/N 97411, 3/8" retaining rings for the reverse rocker in the tower housing. The two 97411 ones are the E-clip style and look different but the 97513 is an external snap ring. Ford/New Holland uses these part numbers on some tractors.


If a part is substituted, be sure it fits the pin well. A person wouldn't want anything to fall off again if that's what happened. If they are all still there then it's a mystery about where it came from.

[nomadpsd]

Originally Posted by MALAK

Probably within a month or two. I literally just started documenting the process. Got a lot of other things going on that hinder my attention to projects like this.

Tom

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Looking forward to your article.

[shew01]

Thanks for all the information in this thread. I'm still sifting through it to determine the way ahead. I really appreciate your interest.

[Markg]

Installed engine & new clutch into trans (Tremec T170FT RTS TOD) in vehicle and pulled off trans top cover and would not come off after a few attempts only able to move up or around a little bit and didn't try and force it. I was able to secure cover back down and now in neutral goes into all gears except reverse with car off. Before rebuilding engine all gears shifted fine. Any suggestions to fix?

[Bob C]

It needs to be in 2nd gear to get the cover off.

[John]

If my memory serves me right, there is also a magnet in the bottom of the transmission case to collect and hold wear metals and may also have picked up some of what you found. Be sure to check that magnet. Transmission disassembly is usually required.

[John]

One must have the shifter in second gear and align all gearsets in the transmission with the shift forks, that is putting the gearsets in second gear only also as well as having the reverse idler in the proper neutral location to properly install the shifter.

[Markg]

Are the forks missing aligned because I have no reverse and all other gears, If idler reverse gear is not all the way back will this cause no reverse? Can the reverse idler gear simply be moved back by sliding it back with a screw driver?

[John]

It does sound as if the reverse idler gear is not aligned with the shifter fork. Check to make sure that both the gearsets and the shifter top are in second gear and that the reverse idler slot is aligned with the reverse fork when installing the top.

JLC

[rotorwrench]

Not only do all the forks have to be in proper placement but the control movement reversing rocker systems also have to be secure and functional. This transmission has a reverse gear rocker system and an 3rd/overdrive gear rocker system. It's not a common set up as most transmission designs go but it was very necessary for allowing this design to function properly for reverse and 3rd/overdrive gears.

The reverse gear selector control fork is long and doesn't have much of a fork end to it. It has to be in the correct position or it won't work at all.

[bettlesr]

The picture of the whole setup looks like the one I have in my car. I got mine from Tim Sheridan in Nunca, MI. His number is 616-837-6477 and his prices were good. His setup uses the stock bell housing, and doesn't have to cut the crossmember. I just cut off the upper and lower ears on the cover of the bell on the front of the drive shaft. He will also shorten the driveshaft if you want or you can have it done locally. The only other thing required was to put two washers under the brake cross shaft to lower it slightly. I went with the trans with the 3.01 first gear and middle overdrive ratio. With a bored and reworked engine, it can still pull up hills in OD. Gets a lot quieter when I put it into OD.

[F1_1950]

Originally Posted by Alaska Mike

Just talked to Gary Bernard yesterday, and yes he is still doing these transmissions. I just about have mine in. Gary does a great job on these. Only three modifications so far, brake cross shaft, and shortened torque tube and shortened radius rods. Gary did the torque tube and brake cross shaft. First Class guy! He has been very helpful!

Did you have the T170 output shaft machined-splined and cut locally?