Ouchhh!! Tr3650 grinding 2nd and 4th gear

Jayystangz

New Member
Established Member
Joined
Jul 9, 2018
Messages
16
Location
Vallejo ,California
So to my Surprise today while minding my business I decided to do a quick first pull (since it was in the shop)my 01 Cobra all went good until 3rd to 4th grinded horribly OUCHH!! Yup brand new clutch and everything about 1k miles or so and clutch in and try and change gear and Nope not happening. Came to a stop and tried going into first and I worked fine then tried just cruising 1st to second and nope again (GRINDDDD) at this point I was Fuming so I went ahead and tried to pull over and then let it sit for a second and turned it back on and BAMMM! 1st 2nd 3rd 4th 5th all Beautifully done and well I’m familiar with this happening before same exact thing happened to my last transmission so you can all imagine how I felt to have this happen. Please Plase PLEASE !! Someone one pitch in .2 cents it’s geting me Mad at this point I don’t want to sell the car but Honestly this is Annoying 2 transmissions and same exact issue. ? Could it be coincidence or !?
 

52merc

Well-Known Member
Established Member
Joined
Nov 15, 2000
Messages
580
Location
Calgary, Alberta, Canada
What are you using for oil? The carbon fiber clutches in the synchronizers are very fussy about the oil. There is a lot of different thoughts on what oil to use.
 

V6&V8SHO

Well-Known Member
Established Member
Joined
Feb 15, 2005
Messages
1,367
Location
IL
I couldn’t stand my 3650. T56 swap was one of the first mods on my 01 Cobra.
 

Jayystangz

New Member
Established Member
Joined
Jul 9, 2018
Messages
16
Location
Vallejo ,California
What are you using for oil? The carbon fiber clutches in the synchronizers are very fussy about the oil. There is a lot of different thoughts on what oil to use.
Currently I think the shop used dexton ,I believe but I’m not too sure might just start there
I couldn’t stand my 3650. T56 swap was one of the first mods on my 01 Cobra.
I’m 100% with you on that but sadly I can’t afford that right now lol
 

CobraBob

Authorized Vendor
Established Member
Premium Member
Single Barrel Sirs
Joined
Nov 17, 2002
Messages
105,349
Location
Cheshire, CT
Ok, just wanted to check. I know the TR-3650 can be clunky sometimes when it's cold.
 

FIREBALL

Active Member
Established Member
Joined
Mar 5, 2016
Messages
509
Location
Calif
Sound like something came apart or broken inside, like bushings or bearings or syncros.

Is the T56 really that much better? Ive read lots of post on other sites that complain about the same problems with the T56. From what Ive read the T5 is the smoothest shifting, but its not strong enough for high H.P.
 

Jayystangz

New Member
Established Member
Joined
Jul 9, 2018
Messages
16
Location
Vallejo ,California
Sound like something came apart or broken inside, like bushings or bearings or syncros.

Is the T56 really that much better? Ive read lots of post on other sites that complain about the same problems with the T56. From what Ive read the T5 is the smoothest shifting, but its not strong enough for high H.P.
Well I see tons of Strongly Moded 03-04 Cobras with them still so I’m guessing they are lol and I mean I would hope a 6 speed would be better I hateeee 5th gear lol I get it’s meant to cruise but God!!! Any slower and I might open the door and pull a Fred Flinstone lol
 

Jayystangz

New Member
Established Member
Joined
Jul 9, 2018
Messages
16
Location
Vallejo ,California
Sound like something came apart or broken inside, like bushings or bearings or syncros.

Is the T56 really that much better? Ive read lots of post on other sites that complain about the same problems with the T56. From what Ive read the T5 is the smoothest shifting, but its not strong enough for high H.P.
But Yea as to the braking something i really don’t know what brakes this is 2 transmissions same gears same problem EXACTLY the same it’s weird because this time it’s been 2 days and I’ve moved the car around and it’s driven perfect no pop out or grinds so I’m just baffeled could it possibly be a sensor or part of my tuning since I have a Basic SCT tune
 

52merc

Well-Known Member
Established Member
Joined
Nov 15, 2000
Messages
580
Location
Calgary, Alberta, Canada
I had my TR-3650 transmission repaired under warantee when it was only 3-4 months old. The 1-2 shifter fork was replaced along with all four forward gear blocker rings. There was a TSB on the shifting issue. It shifted better afterwards, but was still notchy and had a tendency to grind, especially when cold, the 1 to 2 shift. At that time lots of people were recommending GM Synchromesh oil. I just couldn't put anything GM in my car, so I changed it out to Royal Purple Synchromesh. It helped some and I'm still running it today. The transmission still doesn't like the very first 1 to 2 shift when I start out. I just baby it for the first few shifts. When warm it shifts OK. When really hot it shifts great. It also shifts better if I shift quickly from gear to gear rather than easily.

I believe the general problem with these transmissions is getting the blocker rings to release off the clutch cones. If the blocker ring sticks to the cone it is rotating at the same speed as the gear. Normally, the blocker ring floats free from the gear clutch cone when the gear is not engaged. When shifting, the syncho ring needs to mesh with the blocker ring first, then gets pushed against the clutch cone to increase or decrease the gear speed and allow a smooth mesh to the next gear. The grinding noise happens when blocker ring is stuck to the cone, and therefore rotating at gear speed instead of floating. First and Second gears have a dual clutch setup while Third, Fourth, Fifth, and Reverse all have a traditional single clutch arrangement.

The TR-3650 seems to be really picky about the oil used and the oil fill level. The Tremec service manual recommends Mobil 1 Synthetic ATF or Dexron III and fill is 3.8 L [1 US gallon]. The Ford manual says Synthetic MERCON (E6AZ-19582-B) and fill with 3.6 L [7.5 pt].

I believe the T-56 uses the same type of carbon fiber blocker rings as the TR-3650 so it should have similar characteristics. Everybody says the Magnum transmissions shift "like butter" and are much better than the T-56 so I assume the blocker ring design is different. I'm not sure how much more money they are over the T-56, but it seems that it may be worth spending the extra money if your going to buy a new 6-speed.
 

Jayystangz

New Member
Established Member
Joined
Jul 9, 2018
Messages
16
Location
Vallejo ,California
I had my TR-3650 transmission repaired under warantee when it was only 3-4 months old. The 1-2 shifter fork was replaced along with all four forward gear blocker rings. There was a TSB on the shifting issue. It shifted better afterwards, but was still notchy and had a tendency to grind, especially when cold, the 1 to 2 shift. At that time lots of people were recommending GM Synchromesh oil. I just couldn't put anything GM in my car, so I changed it out to Royal Purple Synchromesh. It helped some and I'm still running it today. The transmission still doesn't like the very first 1 to 2 shift when I start out. I just baby it for the first few shifts. When warm it shifts OK. When really hot it shifts great. It also shifts better if I shift quickly from gear to gear rather than easily.

I believe the general problem with these transmissions is getting the blocker rings to release off the clutch cones. If the blocker ring sticks to the cone it is rotating at the same speed as the gear. Normally, the blocker ring floats free from the gear clutch cone when the gear is not engaged. When shifting, the syncho ring needs to mesh with the blocker ring first, then gets pushed against the clutch cone to increase or decrease the gear speed and allow a smooth mesh to the next gear. The grinding noise happens when blocker ring is stuck to the cone, and therefore rotating at gear speed instead of floating. First and Second gears have a dual clutch setup while Third, Fourth, Fifth, and Reverse all have a traditional single clutch arrangement.

The TR-3650 seems to be really picky about the oil used and the oil fill level. The Tremec service manual recommends Mobil 1 Synthetic ATF or Dexron III and fill is 3.8 L [1 US gallon]. The Ford manual says Synthetic MERCON (E6AZ-19582-B) and fill with 3.6 L [7.5 pt].

I believe the T-56 uses the same type of carbon fiber blocker rings as the TR-3650 so it should have similar characteristics. Everybody says the Magnum transmissions shift "like butter" and are much better than the T-56 so I assume the blocker ring design is different. I'm not sure how much more money they are over the T-56, but it seems that it may be worth spending the extra money if your going to buy a new 6-speed.
That made sense once you explained that all sounds right ( greatly done BTW ) guess I’m going to do a drain and fill I used to run royal purple Synchromesh in my old 03 GT with a tr3650 Thanks for the help I’ll try that out
 

FIREBALL

Active Member
Established Member
Joined
Mar 5, 2016
Messages
509
Location
Calif
Well I see tons of Strongly Moded 03-04 Cobras with them still so I’m guessing they are lol and I mean I would hope a 6 speed would be better I hateeee 5th gear lol I get it’s meant to cruise but God!!! Any slower and I might open the door and pull a Fred Flinstone lol

I was mentioning 2 different transmission----I was saying that the old T5 has been reported the smoothest shifting but not strong enough for high H.P.
 

FIREBALL

Active Member
Established Member
Joined
Mar 5, 2016
Messages
509
Location
Calif
My old 3 and 4 speed borg warner and Muncies were the best shifting trans and with a Hurst syncrolock shifter they really did shift smooth and fast, and their technology is over 55 years old and it hardly matter what oil you put in them!! These tremecs are so frustrating, they are poorly designed, I think the engineers over thought when designing them. Tremec has changed their opinion on what oil to use at least 3 times (and depending on who you talk to at Tremec), then there is what is the correct oil level issue and the fiber syncros. It tells you there has to be something wrong with the design and engineering when they decided you need to put less oil in it to shift better. They are the worst shifting trans I have ever drove. Oh yeah, forgot to mention the whiny gears that sound like a crash box out of an old dump truck.

Other than the update snycros and fork is there anybody or any place that can trick these things out to shift smooth or what other trans will bolt up that has a history of shifting smoother?
 
Last edited:

Jayystangz

New Member
Established Member
Joined
Jul 9, 2018
Messages
16
Location
Vallejo ,California
Just to keep everyone updated yesterday night I went out and car did the same Thing again and today when I got to work I went ahead and tore apart the shifter bezel and cover I found my adjusting bolt and but LOOSE and hiring the shifter handle , I fixed it and drove it around and nothing yet I’m currently at work I’ll drive further today and see what happens
 

Users who are viewing this thread



Top