727 Question

[mopar0166]

Through all the stuff that I know about 727 transmissions, and their common faults etc.    What's the best option to go with?   I have gone through 4 with not racing it or doing crazy stuff.  burnouts yes, spirited driving yes - If ya cant do that stuff in a muscle why am keeping this thing.  Ive been told that since I drive in manual sometimes, that it has killed my transmissions, I doubt that.   especially with an cheetah auto/manual VB and all the upgrades made to the internals. 

Looking to see what this crowds recommendations are, I'm extremely careful on what I'm dumping money into this time.   

[Paul G]

The 727 is a very strong transmission. If you are having a problem keeping them alive I would look for other reasons. First and foremost is cooling. Make sure the transmission cooler is clean and flowing fluid properly. Heat is the biggest killer of a transmission.

[mopar0166]

Thought I had addressed the heat on my last rebuild, I added new braided lines with external cooler.   The heat concerns were brought up last time I had an issue and I moved away from the sticks lines and rad cooling.   

I appreciate your comments though.  I guess frustrated or ticked off  isn't the best words but I'd like to find what combo will work best for me so I won't have to piss away even more money in two years.  No better please to get that opinion then right here.

[mopar0166]

I guess another question is strength differences between 727 and 833 manual.   I'm looking at all angles, tired of wasting money.

[c00nhunterjoe]

What failed in the 4 transmissions you reference?
What exactly is done to the trans.
How much torque are you putting through it.
Are you doing your burnouts in 1st gear?

[Paul G]

Have you talked with some of the bigger trans builders? They may have some ideas or solutions for your problem. I have been pretty rough on my 46RH, and the 727 before it. Burnouts, full throttle shifting, etc. Never a problem. My 360 engine makes 300HP and 400 Foot pounds. That is not huge power, but I am not easy on the car.  

PATC, https://transmissioncenter.net/,

Monster, https://www.monstertransmission.com/TF8-727-Transmission-Heavy-Duty-2WD_p_5032.html#.W6JiGGhKjIU,

TCI, http://www.tciauto.com/

Coon hunter brings up some good questions. When doing a burn out dont let up on the gas to stop the burn out, you should let the car roll away and shift before letting up. Have all these rebuilds been using the same trans case?

[mopar0166]

What failed in the 4 transmissions you reference?

1- SB 727/318 SB  - was the original it was a stock transmission / lots of miles - used it till it went, clutches were shot
2- SB 727/318 SB - Original transmission was rebuilt using a TCI rebuild kit, hard parts were in good condition.  transmission failed a year later when reverse and 1st started to slip.
3- BB 727/440 BB - Transmission was a new TCI Super street fighter, torque converter was 2400 stall (new) and new cooling lines and rad.  This failed about a year later, upon rebuild it was determined it was getting too hot,  replaced the clutches, seals, drums bands etc.
4 -  BB 727/440 BB - After rebuild of TCI transmission - it lasted a good 2 years. I noticed that it was slipping in first and then in reverse, reverse was making a whing noise as well.  I looked at the fluid at the dipstick and it looked a little dark but not black as the previous three times.  fluid level was good as well.   I then dropped the pan and saw some dirty fluid dirty filter and some debry.   I have stopped there for now.  

What exactly is done to the trans.

They all received a good cleaning and full rebuild each time.  After #3 I replaced the pump and torque converter and added braided cooling lines an fittings and external cooler.  The upgraded internals were recommendations from cope and TSR racing at the time because I had enough crap dealing with TCI.


How much torque are you putting through it.

I don't have a documented torque number   it a 440, 30 over bore, edelbrock power pack package, compression 10:1 speed pro pistons etc.  So torque is above stock numbers but I do not know exactly.

Are you doing your burnouts in 1st gear?

Yes I do burnouts in first gear, and as I'm researching the 727 more and more I'm reading that's a bad idea.  Most of what I was reading is that it should be done in 2nd.  I never heard of this but this justification made sense.  

[mopar0166]

Have you talked with some of the bigger trans builders? They may have some ideas or solutions for your problem. I have been pretty rough on my 46RH, and the 727 before it. Burnouts, full throttle shifting, etc. Never a problem. My 360 engine makes 300HP and 400 Foot pounds. That is not huge power, but I am not easy on the car.  

PATC, https://transmissioncenter.net/,

Monster, https://www.monstertransmission.com/TF8-727-Transmission-Heavy-Duty-2WD_p_5032.html#.W6JiGGhKjIU,

TCI, http://www.tciauto.com/

Coon hunter brings up some good questions. When doing a burn out dont let up on the gas to stop the burn out, you should let the car roll away and shift before letting up. Have all these rebuilds been using the same trans case?

I have talked to those three in detail before doing the last rebuild.  TCI I will never deal with again, they are useless, Monster was great but after speaking to their techs, and having the guy who was gonna do my rebuild talk to them, it was determined to continue with our rebuild instead of having them do it.  I did contact PATC, Cope and TSR as well but it seemed like we had a good game plan. 

It very well could be the few times I was aggressively driving, but it should last longer.   That's why I'm double checking all my facts and getting educated as much as possible prior to any money spent towards any transmission solution.



I really appreciate all the comments!!!!

[c00nhunterjoe]

Ok, so it was 2 units, not 4. Fair enough. Forgot ththe small block as its gone. The 1st tci got overheated and cooked, then rebuilt. Not sure what has failed yet but if 1st and reverse are soft, you kindof already know. Full teardown will tell. Rolling out of a burnout in 1st or 2nd and letting the tires hook is hard on sprags and bands. Depending on what valvebody you have regarding the band. Should finish in 3rd. Time for tear down and inspection before we can really go much further. Do you have a temp gauge on it?

[mopar0166]

I don't have a temp gauge hooked up, I did buy one but omitted on hooking it up stupidly.  c00nhunterjoe, I highly respect your opinion on this and you have never lead me wrong.   I'm not sure when I will get into a tear down of the transmission.  But in the mean time I wanna explore my options, maybe find the best suitable option for the car, engine and driving experience. I've never run through all the gears while doing a burnout, is that in general or a mopar thing?  Of course I'm a mopar guy but gained most of my experience through Chevy guys.  it is what it is.   

Valve body was a cheetah 17676 auto/manual.  I was told at the time that was my best option versus using the TCI one I already had. 

[c00nhunterjoe]

In all reality, the eddy power package is not the biggest power maker. But to be safe, lets say you are making 490 hp/520 ft lbs. I assume you are not running a drag radial or anything super sticky so power to the ground is limited. A mild 727 should easily sustain that given you are not cooking the fluid. I highly suggest installing the gauge, especially if you already have it.
   The reason for the burnouts is the sprag failure. I doubt its the cause for your failures as your case is still in 1 peice. Your vb may have low band apply which helps take the shock off the spragduring a 1st or 2nd gear abuse. Im not 100% sure on the manual/auto ones. Best rule of thumb is get into 3rd before rolling out of the burnout. Its not just 727s that have that type of failure. Gm 4l80s can do it as well but the case grenading is not as popular a problem as a torqueflite. Ive got mine wrapped in kevlar, but im overkill and have alot more hp going through mine on slicks.
  What upgrades to the internals were done? You said cope amd tsr set you up but what was done aside from the valve body.

[flyinlow]

What fluid are you using?

Does the trans cooler get hot after driving?

disconnect rear cooler line , start the engine and see if a steady stream of fluid is returning from the cooler.

Hook up temp Gauge.

When I put a 2500rpm converter in my A518 the temps in the pan went up slightly (15*) when driving with the converter unlocked. About the same power as your  car. Temps 150-180* even if you go the drag strip. Sorry I don't have a temp gauge on the other Charger with a 727.

[mopar0166]

I know the type of fluid was a big thing when I rebuilt it a couple years ago.   I wanna say I used the performance tci fluid.   I think at the end of the day that is what I was persauded towards.   The temp gauge I'll have to deal with once I'm on to the new transmission.     Didn't think of the possibility that te cooler may have gotten clogged and caused an over heating of the fluid.   

Probably Sunday I can run some more tests and see what's what.

[Paul G]

What about line pressure. How is the kickdown adjusted, where are the shift points?

[mopar0166]

That was setup based on trans rebuild manual.  Fsm and kick down was a lobar cable

[Paul G]

Line pressure is very important. I have installed a few shift kits, trans swaps, adjustments, etc. but I am not a trans re-builder so someone will chime in here if I am wrong. Lower line pressure will allow the trans to shift gears quicker at lower speeds, the clutches will slip a little more for easier shifts but causing more wear on them. Higher line pressure will allow the shift points at higher speed, firmer shifts, and actually easier on the clutches.

Line pressure is adjusted with the kickdown rods or cable. Something to consider. And it must be set for the engine and combination you are using. The FSM is designed for a stock application. You are no longer stock.   

[mopar0166]

Thanks for the info.   I suppose I could fill it back up and test the pressures it's at now.  I really don't have a good grasp of what it was after rebuild.  As I was the rebuilder.  But I can try to find out.

[Paul G]

What I am saying is if you have been running the trans with quick shift points, which equals low line pressure, it can prematurely wear out the clutches.

[TommyGun]

This is pretty basic, but are you flushing out the cooler and lines when replacing the trans? Old fluid holds shavings and junk that can ruin a fresh trans..

[mopar0166]

external cooler and lines were all new on last build as well as VB and torque converter and pump

[John_Kunkel]

Ive been told that since I drive in manual sometimes, that it has killed my transmissions, I doubt that.   especially with an cheetah auto/manual VB and all the upgrades made to the internals. 

Kinda depends on how often "sometimes" is. Regardless of anecdotal tales to the contrary, manually shifting a TF that's not properly modified is hard on the trans, especially the rear band which is used in Reverse and you stated a couple of your failures were in Reverse.

The "manual/automatic" feature in a valve body is just an advertising gimmick; if you think about it, a bone stock valve body is manual/automatic.

[mopar0166]

Thanks john for the reply.  I understand what your saying, and yes I do enjoy shifting manually.     I guess if I were to stay with an automatic then I need to restrain the shifter from manually being dropped into gears etc.    I will have to keep this thread updated as I know more about the failure and how to move forward again.

[c00nhunterjoe]

Or put a manual valve body in it and be done with it.

[mopar0166]

From what I understand that a good option for racing but what about street driving.

[flyinlow]

One of my Chargers  is manual VB (bought it that way) .  Seams to work fine on the street.  I wondered  about wearing out the rooster comb shifting, but no problems yet.  If you forget to down shift at a stop sign, it is kind of doggy acceleration starting in third gear, but outside of a little more heat from the converter churning more the transmission does not seam to suffer.