need transmission help

[ShadowBolt]

Does anyone have an idea why we (Jay and I ) are tearing up transmissions? I went to the Astro A5 and got about four or five years out of it but when it broke Tony could not get any parts for it so I went to the 600RR. I assumed since this transmission was supposed to be able to handle so much more HP/TQ than we make in CMC that I was through having transmission issues. I purchased a new unit from Joe Dederichs. I did not like the way it shifted so I spent more money (around $1000.00) getting it fixed. After that it shifted like butter. We never noticed anything until Hallett when it shit the bed. I sent it to Joe and he said it is tore up pretty bad. About $1500.00 to fix but he can't get any parts for it right now (I'm in the same shape with the Torsen T2R I ordered. They are on backorder and have been ). Any ideas if there is something we are doing causing us to tear up transmissions? I change the fluid at the beginning of each year. Is that not enough? I'm tired of working on this car and spending so much money. If it's something we are doing we must figure it out. Any help would be appreciated!


JJ

[mach1]

I had the same issues with my car, well under the tq limit, i broke the cluster and Josh did as well after he got the car IIRC. Seems that with most road race cars transmissions are a maintenance item, SM guys usually get 1-2 years out of the gearbox. What did you spend 1k on to get it to shift better? What's broke now?

[BADVENM]

Interesting topic. Our '86 Mustang has had no issues in 11 years of racing a full Rocky Mountain CMC schedule, including 5 or so Nationals events. We've replaced the clutch a few times in those 11 years and added a road racing 5th gear about 5 years ago.

[ShadowBolt]

I don't know exactly what Joe added to make it shift so much better but it really helped. It may have not been more than $600.00 or $800.00 as I don't keep up with exactly what I spend doing this stuff. You could ask Joe what it is that he did to make it shift so much better. Before it broke it shifted as well as a T5. Jay and I do not even try to shift like Michael does or I don't think we would finish a weekend. I certainly do not push it as far as shifting really fast. I am going to ask Joe what all is broken but I'm almost sure the input shaft is one item.

I was going to switch over to a 3650. Aaron and others have ran it as is from Ford and have had no issues. I talked to Tony at Astro, a guy that owns Pro Force and Joe and they are telling me the 600 should hold up better than a 3650. Hell I don't know what to do. If I'm going to have to replace them every other year I will go back to running a $1800.00 T5 at only 75 lbs. Since we are not drag racing I don't think the 10 spline input shaft is an issue but I have gone through two A5's and a TKO600RR in 10 years of CMC racing. The thing that bothers me is I was getting four years out of the A5 (these were rebuilt units as there are no new A5's) and we were running every event NASA Texas put on (and NOLA three times). In the last two years we have been running the 600 I doubt we have ran in more than six or seven events.......TOTAL! This is the kind of shit that makes me think of quitting. It's not really the money it's all the work to get to the track and then clean up and put it all up when you get home and not getting to race the full weekend due to parts failures. Then of course I get tired of the wife saying "didn't you just buy that transmission brand new (not rebuilt) for $2500.00 less then two years ago and now he is telling you it's torn all to hell"? I assumed a transmission that is rated to hold up to 600 ft. lbs. of torque would last ten years in a 260/310 CMC car. I even remember telling Kathy "well we should be through spending money on transmissions". "This new one is made to handle way more power than the 55 makes". This is why I'm asking if there is something we are doing wrong. I don't know what it would be but how in the hell do we tear it up with so little power? I would hate to have the TKO600 behind my Lightning. I doubt it would make it to the end of the street.

JJ

[ShadowBolt]

Interesting topic. Our '86 Mustang has had no issues in 10 years of racing a full Rocky Mountain CMC schedule, including 5 or so Nationals events. We've replaced the clutch a few times in those 10 years and added a road racing 5th gear about 5 years ago.

What transmission were you running? T5? A5? Hell the guy at Pro Force said if he was me he would buy a new T5. LOL

JJ

[michaelmosty]

I honestly don’t have much faith in the quality of the new Tremec. My 600 was crap out of the box and I had to fight with Tremec for 2 months to fix it under their dime. Joe was great and went to bat for me or I doubt they would have even given a crap.

If I could do it all over again I would have just fixed a few issues on my old 3550 and kept running it. It worked way better as a used unit when put in the car in 2005 than this brand new 600 ever has been.

I’m sorry you are having so many issues Jerry, I wish I had a good answer for you.

[michaelmosty]

Just as an example, the 600 felt worse out of the box than my 3550 did after 12 years of racing, and it was obvious the 3550 needed some work to fix some issues.
After Tremec fixed the 2-3 and 3-4 issues it felt way better but it has never felt like a perfectly working transmission.

[BADVENM]

We're running a non world class T5. I think we changed the synchronizers one or twice in 10 years when we had some clunkiness going into 3rd. Are all Texas region races standing starts? Are you power shifting? What shifter are you using? Is it one with adjustable stops and is it set up properly?

[Suck fumes]

In my opinion the 3650 is the most reliable easy to quick shift transmission i have ever used in any mustang pre 2014. I spent about $900 on new parts to rebuild it when I first built the car just as preventative maint but there was technically nothing wrong with it even though it had 110k mi on the car. Making sure the clutch is adjusted right it also critical. Need to make sure when clutch pedal is all the way down that it doesn’t try to lurch when putting into gear at a stand still.

Also i have always used the steeda triax shifter cause it has overshift stops that are adjustable.

[Alien]

I really have no intellegent Ford input, but what engine and trans mounts are you running? Solid, poly, or rubber? My engine ones are still rubber (I think... either way def not solid) and T5 trans is poly. Thought is the softer mounts absorb some of the shock better than solid.

[ShadowBolt]

We're running a non world class T5. I think we changed the synchronizers one or twice in 10 years when we had some clunkiness going into 3rd. Are all Texas region races standing starts? Are you power shifting? What shifter are you using? Is it one with adjustable stops and is it set up properly?

Only two of the four races (when we get four races) are standing starts. We have never powershifted. The shifter is the one that comes with the transmission. I adjusted it when I first bought the transmission and have not messed with it since. I ask Joe if he could tell what caused the unit to take a shit and he said he could not tell. I assume if it was the shifter not adjusted properly he would have been able to see it.

JJ

[ShadowBolt]

I really have no intellegent Ford input, but what engine and trans mounts are you running? Solid, poly, or rubber? My engine ones are still rubber (I think... either way def not solid) and T5 trans is poly. Thought is the softer mounts absorb some of the shock better than solid.

I ran rubber engine mounts for nine years and just switched to the solid this year. The transmission mount is a Stifflers https://lmr.com/item/STF-TCBM20/mustang-stifflers-adjustable-transmission-crossmember-99-04.

JJ

[ShadowBolt]

In my opinion the 3650 is the most reliable easy to quick shift transmission i have ever used in any mustang pre 2014. I spent about $900 on new parts to rebuild it when I first built the car just as preventative maint but there was technically nothing wrong with it even though it had 110k mi on the car. Making sure the clutch is adjusted right it also critical. Need to make sure when clutch pedal is all the way down that it doesn’t try to lurch when putting into gear at a stand still.

Also i have always used the steeda triax shifter cause it has overshift stops that are adjustable.

I'm leaning on going with the 3650 but I have always been told that with long tubes I would have to pull the engine to change the clutch! That means if you lose a clutch at the track (like at Hallett) you are screwed. Now we have never had a clutch issue. In ten years I have changed the clutch disk only once (just for shits and giggles) and I'm still running the same pressure plate that I installed with the first A5. We are not hard on clutches but tear up transmissions. Maybe it would be worth it to go to shortys and the 3650.


JJ

[Suck fumes]

if your crafty you can just undo one header and get the gearbox out without yanking motor. But I’ve never had to deal with it cause the 3650/clutch never give me problems. I have urethane mounts. If you go 3650 make sure you run Royal Purple ATF and dont fill it till it runs out the fill hole. I usually have a half a pinky room when putting finger in fill hole to feel where fluid is. There is an actual fill spec on google somewhere. Don’t run redline or any of the manual synchromesh garbage.

[Sook]

I have had good luck with my used 3650 in my S197 track car.

The 3550/TKO in the CMC car shifts terrible compared to a T5. The mechanism in the 3550/TKO is complete junk. They use massive shift lugs with a very sloppy mechanism. I guess a plus side is that it probably won't wear out since their all iron. A common mod is to blue print these parts to tighten them up. Definitely setup for drag racers bang shifting the thing, which was a point of failure in drag race application T5s.

The 3rd gear on the front of the output shaft is what always breaks in the T5 and TKO boxes (for me at least). I think as the box heats up and and becomes longer. The shafts can move and bend more reducing tooth engagement. Enough cycles like that and it'll pop some teeth off. Real race application transmissions have a little dog-bone thing that joins the two shafts together so they can't spread as easily. I did split an output shaft in a T5Z at hallett three years ago and it ended up splitting the entire case.

Jerry, is your drive shaft in good shape? Vibration through the output shaft of the trans could cause issues. The output shaft is also very long, making it more susceptible to vibrations from 'low speed' things like the drive shaft.

- Josh

[mach1]

Jerry, have you checked your bellhousing to crankshaft alignment? If all of your problems revolve around the input shaft maybe the issue is there

[ShadowBolt]

Jerry, have you checked your bellhousing to crankshaft alignment? If all of your problems revolve around the input shaft maybe the issue is there

I had a machine shop make me some offset dowels so I could dial in the alignment. That is not the issue but I assumed it was when I lost the first transmission after starting to use the Quick-Time bellhousing.

JJ

[Supercharged111]

We're running a non world class T5. I think we changed the synchronizers one or twice in 10 years when we had some clunkiness going into 3rd. Are all Texas region races standing starts? Are you power shifting? What shifter are you using? Is it one with adjustable stops and is it set up properly?

To be fair, we're down about 30whp from the TX guys here and don't get as much heat as they do. That may play a role as well. I'd be curious what the other regions' Ford guys are seeing for transmission failures.

[BADVENM]

11 YEARS (full region race schedule) no problems, including 5 or 6 National championship weekends and in some cases 4 day events (test and tune, 45 minute races, etc). ShadowBolt isnt lasting a season, two at best. Surely our altitude isnt making that much of a difference.

[Supercharged111]

11 YEARS (full region race schedule) no problems, including 5 or 6 National championship weekends and in some cases 4 day events (test and tune, 45 minute races, etc). ShadowBolt isnt lasting a season, two at best. Surely our altitude isnt making that much of a difference.

Who knows?

[blk96gt]

My car still has the stock T45 that came with the car and there's no indication that it's on its last leg. The car had ~63k miles when it was turned into a race car in 2010.

[t500hps]

To be fair, we're down about 30whp from the TX guys here and don't get as much heat as they do. That may play a role as well. I'd be curious what the other regions' Ford guys are seeing for transmission failures.


I'm running a t45. Bought the car with a used t45 in 2012 and immediately had the spare rebuilt with "good" parts (Zak at the t45 source built it). Installed that winter of 2012. In winter of 2018 I had been having trouble getting the car to shift if we had slow double yellows but it would shift fine when back at high rpm....so I had it rebuilt again. Been fine since.

The t45/3650 are a absolute bitch to remove around long tubes.......but it can be done. We've pulled/installed several but it takes alot of maneuvering to twist/rotate to get the bellhousing up in there.