3650 tear down/install

rocky61201

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I'm in the middle of rebuilding my TR3650 and decided to tackle the job myself because of this thread. I've owned my 06GT since 08 and joined this site shortly thereafter. Lately I've noticed quite a few new members buying up our used GT's and starting doing their own maintenance/upgrades. Do not put that R*y#l Pu^rple stuff in your transmission. It will wear down/eat up the carbon fiber linings on your syncro blocking rings. The carbon fiber lining is there for one purpose, to create friction and stop the free spinning gear your are trying to shift to.

The TR3650 I'm rebuilding now is the original I blew the syncro's on about 3 years ago. It's been sitting ever since. I put that RP stuff in long ago before I new any better. I've got the trans completely disassembled and the blocking rings spin freely when pressed against the gears instead of grabbing on and stopping the gear from spinning when attempting a shift. That's where the grinding comes from when shifting.

Anyway this thread and pics are great if you want to rebuild your TR3650. There are also you tube videos you can search for. Special tools you will need: lock ring pliers (snap ring pliers won't cut it), drift punch, large bearing separator plate, 2 jaw puller, and 2 or 3ft of threaded rod from home depot because the output shaft is about 2/3ft long. A 1 1/4 inch socket to remove the flange. Don't buy an impact socket, it will be too thick to fit into the recess in the flange! Also, these service manuals are a big help too.

Last thing, I got my parts from Stan at pro performance. He will sell you only what your need, instead of an entire rebuild kit that you only need 3/4 or 1/2 of the parts from. http://www.pro-forceperformance.com/

View attachment TR3650 Output Shaft.pdf

View attachment TR3650 Assembly.pdf

View attachment TR3650 Disasembly.pdf
 
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SPeace-ATL

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This is a great thread - I approve of what has been said here!

I want to add a few "Tips & Tricks" and perhaps reinforce a few things that were said.

For ANY TR3650 the fluid fill is 3 liters, or 3.2 quarts from a dry fill. This is NOT a fill to the fill plug transmission. That puts too much fluid in and it will not shift into second gear smoothly when cold if it is overfilled. This is a revision by FORD and by Tremec.

The official TR3650 fluid is Mercon-V which is a synthetic blend and is fine for this transmission. If you want a synthetic fluid go with the Mobil-1 Synthetic Multi-Vehicle ATF. This is reportedly what Tremec used when developing the TR3650 anyway. The Pennzoil for Synchromesh Transmissions is approved by Tremec and won't hurt it but it is thicker and is old technology so it doesn't have the cleaners in it like ATF and breaks down pretty quickly so if you want to use this you should change it frequently. They get pretty black inside pretty quickly when using this fluid. All three of these are approved by Tremec. Avoid all other fluids. I've seen a lot of damaged rings in TR3650s that have the purple colored fluid residue in them despite many good reports from people who have just switched to it. They never report back later... I don't have experience with Redline fluid in a TR3650 one way or the other, but there are three great choices of fluids that are approved. Why not stick with them.

The Syngear-II mentioned above is also packaged as G-Force GF-2000. It does not hurt the TR3650 and does quiet some gear noises. G-Force uses this additive when you have their custom TR3650 gear kit (mentioned above). Those gears are not perfectly quiet and the additive helps.

For the 2005-2010 that rubber seal under the output shaft flange is a problem if you are using the flange nut to draw the flange back onto the output shaft. This was mentioned in a post above but I want to say it again. Put it together WITHOUT that seal, then remove the nut and steel washer, install the flat rubber seal, washer and flange nut and torque to specs. Otherwise, that rubber flange washer will be shredded.

Now, I will add that putting that flange on with the nut is very hard on the threads on the nut and the output shaft. It is much safer if you have access to a hydraulic press with a tall enough throat to just put the transmission in the press and press that flange on that way.

Shift Forks and Rails.
Don't forget that there are THREE interlock pins in the shift rails but only two of them can be seen. The third one is smaller and is inserted completely inside the middle rail and is often lost by those who don't know it is in there.

The order of the fork rails is different for an 01-04 than an 05-10.
The 01-04 is 1-2, 3-4, 5-R and the 05-10 rails go in as 3-4, 1-2, 5-R.

You can leave the forks on the rails when disassembling if you lift the 3 rails out WITH the main shaft as a grouping. Likewise, you can reinstall them as a group. Trying to put those roll pins into the forks while the main shaft is vertical is pretty awkward.

The tool for the DO Not Remove Bolt is available from Snap-On.
(Torx Security Plus 5-lobe, hollow tip) You can leave this bolt and reverse idler gear in place but you have to coax that rear counter shaft bearing off the shaft at the same time you lift the main case off. It is suggested to "hook" the cage of that bearing so it can be lifted up as the case is lifted. The problem is this bearing hits the reverse idler gear and interferes with the removal of the case. That bearing is a slip fit and is not pressed on so it can be coaxed off. Perhaps laying it horizontal may help so that gravity isn't holding the bearing back while lifting the case. I remove the bolt with the special tool.

Lastly, that lock ring that holds the small fifth gear on the main shaft is a problem. If it is stretched even the slightest bit they are prone to coming off which allows the small fifth gear to slip down the main shaft. Once slipped, it will shred all the teeth off of both fifth gears and make a mess of your freshly built transmission. I recommend always replacing it once removed.

Enjoy! - Stan
 

ABAuto

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@BeachMonkey100, Thanks for these visuals, awesome! Need a little guidance been building trans for 40 some years, fuirst tr3650... got it back together, but missed the f'n check balls... can you give any tips/help on what to do... am I going to have to take this whole thing apart again... thanks
 

rocky61201

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I haven't seen beachmonkey100 around here in awhile. I'm not sure which one or how many of the check balls you lost (all of them???). No matter, I'm pretty sure the only person you can get them from is Stan at Pro Performance. He can probably sell you just the check balls and no other extra crap you don't need for probably just a few bucks total.

I have no advice or shortcuts to give you. You are going to have to take the whole thing apart again. Ask Stan for a new set of double roll pins since you're gonna have to tap the other news ones out again. Again only a few bucks for piece of mind.

In the end your mistake is probably only going to cost you ten dollars total shipping and tax. Not a big deal. And you will probably do a better job measuring end play since this is your second time around.

EDIT - I just remembered your biggest expense. Another tube of RTV, lol...

Here is Stan's website.

http://pro-forceperformance.com/tr3650.htm
 
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SPeace-ATL

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Just the three little check balls? Honestly, all they do is keep the three thrust washers from spinning on the shaft. As much of a detail person as I am, I can't say that it would hurt anything to have left them out. However,

I can't allow myself to leave them out since I have a reputation for quality to uphold. (Many of you know who I am...)

Also, on the newer custom G-Force TR3650 gears, they did not include the detent hole for the check ball on the cluster shaft under the large fifth gear thrust washer. I guess they don't consider it important.

On a T-5 there are two similar thrust washers on the main shaft and they are not locked with a check ball either.

Stan

PS:
Thanks rocky61201
 

rocky61201

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This started in the what has pissed you off today thread. Last week a .75 cent lock ring failed allowing 5th gears to float against each other and the pic below is the result. I have a spare 3650 I picked up years ago in the junkyard for about $350 bucks. I've been rebuilding and swapping them out ever since using knowledge from this forum. Saved a ton of money. So I scavenged 5th gear out of my spare 3650 and got them in. Still no luck. I'm guessing some metal chards got thrown around and damaged the other gears.

Fast forward to today and got some work done! Tore down my spare 3650 I removed a couple years ago because it was getting noisy. Only failure was a damaged input shaft pocket bearing. Scored up the forward end up the output shaft a little but I should be able to polish it up ok. And I have a new pocket bearing in my spare parts bin. Score! Going to get another tube of RTV and get this back together today and hopefully have the Mustang back up and running in less than a week and didn't cost me nothin! (Sorry Stan at Pro Force Performance lol). Unless this doesn't work and you might be hearing from me.

If you plan on keeping your manual trans Mustang for a long time I suggest picking up a spare 3650 from the junkyard and use this forum to learn how to rebuild. It ain't difficult. The service manual is around 50 pages with pics for every step. If you can pass HS Algebra you can do this!

IMG_1594.JPG

IMG_1597.JPG

IMG_1596.JPG

IMG_1598.JPG
 
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SPeace-ATL

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Looks like you are ell on your way! Yes, that clip will break and especially if it has been spread a bit when it was last removed.

Having a spare for parts is a great idea. I thought I would share about compatibility of parts through the years. I am thinking particularly about the gears themselves.

For 2001 and 2002 they used an early gear set that was updated in 2003. Either gear set is fine in my opinion, but there are three gears that are NOT interchangeable with a 2003 or newer TR3650. Those gears are First Gear, and the big Reverse Gear on the main shaft, the Cluster Gear, and the Reverse Idler Gear. The ratios are the same, but they changed the shapes of the teeth...

If your transmission does not have a tag to tell which year style it is you can look on the cluster shaft and spot the difference. The smallest gear on the cluster is a wide gear that is a combined first and reverse gear. For the 2003-2010 style cluster shafts there is a small "step" you can feel (and see) if you run a finger along the tips of the gear teeth. There is no step on the 01 and 02 gear set. Of course, the input shafts are LONGER for the 05-10 units. Also, for 05-10 the main shafts, case pieces internal shift linkage and shift forks are all slightly different from the 01-04 units.

A 2001 TR3650 is tagged TCET1265 and a 2003 is tagged TCET1789.

Also, there are two fifth gear pairs used from the factory in the Mustang TR3650 transmissions. 2001 and 2005-2010 used the 0.68 fifth gear and the 2002-2004 units used the 0.62 fifth gear.

There is one exception in that the TCET5850 is a 2005-2010 style TR3650 with a 0.62 fifth gear. I must add that in all of the TR3650s I have opened over the years, I have never encountered a TCET5850...

Stan
 

rocky61201

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Thanks Stan. The transmission I have apart in my garage right now has that "step" on the cluster shaft. My other "ruined" transmission is still in the car. I'm gonna swap them out in a couple days. I'm pretty sure the guts are identical on both of them. I don't have the original tags on either. Took them off and lost track of them years ago. After this episode I'm considering putting a tack weld on each of the 5th gear lock rings, lol,
 

Midlife Crises

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I try not to use lock rings, snap rings and roll pins more than once. Sometimes the replacements don’t look as good as the original and might not be of equal quality. Frustrating!
 

rocky61201

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same here. I guess that's why they're pilling up in my parts bin. I should just throw them away so I won't be tempted to reuse them.
 

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