456 auto-tranny by GM | FerrariChat

456 auto-tranny by GM

Discussion in '456/550/575' started by parkerfe, Feb 12, 2008.

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  1. parkerfe

    parkerfe F1 World Champ

    Sep 4, 2001
    12,887
    Cumming, Georgia
    Full Name:
    Franklin E. Parker
    Did you read the letter in Hemming's Sports and Exotic Car magazine about how the $50k slush-box in the 456 was made for Ferrari by GM and that all interior parts are interchangeable with the Cadillac auto-transmission at 1/100th the prices charged by Ferrari...the article claims that only the outer casting is different...
     
    stevegtsi likes this.
  2. 2000 456M

    2000 456M F1 World Champ

    Sep 29, 2007
    12,600
    Portland, OR
    Full Name:
    Allan
    Can you post it? Thanks.
     
  3. Pcar928fan

    Pcar928fan Formula 3

    Jan 21, 2008
    1,702
    Austin, TX
    If true that would be AWESOME! I read somewhere else that the trans is made by Allison I think it was and that there was NO interchangeability between it and any other box. Ferrari does have along history w/ GM auto boxes though! It would be AWESOME if that were the case, I would be WAY less hesitant to buy a 456 GTA...that won't help put money in my pocket to do it, but I certainly would worry MUCH less!
     
  4. ernie

    ernie Two Time F1 World Champ
    Lifetime Rossa Owner

    Nov 19, 2001
    22,574
    The Brickyard
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    The Bad Guy
  5. RawAutos

    RawAutos Karting

    Jan 24, 2008
    92
    Raleigh, NC
    Full Name:
    Josh Lewis
    I thought I read this years ago... Not positive. I do remember being told that the 456 did have a GM sourced automatic tranny though. I could be wrong but, that is what I remember.
     
  6. otaku

    otaku Formula 3

    Aug 12, 2005
    1,391
    Boise,Idaho
    Full Name:
    Josh
    Hell if anything thats probably good news (cheaper to repair/replace) just as long as they keep making the engines themselves and continue to turn out stylish rides I don't care where bits and pieces are from (granted a tranny is fairly important) but it is an auto not an automanual or manual so its less of an issue to me.
     
  7. goldsax

    goldsax Karting

    Nov 30, 2005
    51
    any progress with the info on this thread?
    really interesting
     
  8. alberto

    alberto Formula 3

    Aug 25, 2001
    2,395
    San Diego
    Full Name:
    Alberto
    It's also in the current Sports Car Market magazine, in the letters section. Someone wrote in that they rebuilt their transmission from GM parts.

    Alberto
     
  9. aviaid

    aviaid Rookie

    Jul 28, 2005
    6
    Calabasas, CA.
    Full Name:
    John
    Derived from a 4T80E transmission out of a 90's Cadillac. The main scavenge filters are cheap and easily accessible from underneath the car when the pan is removed.
     
  10. ChipM

    ChipM Rookie

    Jan 1, 2013
    40
    Spartanburg, SC
    Full Name:
    Chip McLeod
    456 GTA Driveline/transmission noise - I know lots of these are old threads and this will be a long post but maybe this info will help others. I have recently posted about working on the torque tube and autobox of my car, so this is a more detailed write up. I have a 98 456 GTA (a very late non-M). It has had a small noise in the driveline since I bought it. The noise is not a grinding but an intermittent "rattle", almost like a loose marble somewhere, then quieter other times, not noticeable to anyone but me. I happens in P, R, D, although it did seem worse sitting still in D with a foot on the brake. Last summer after ruling out exhaust, shields, etc., I decided to pull the TT (torque tube) down after reading about the bearings in it. Both autos and 3-pedal cars have the tubes, although the shafts and bearings are different. I had it up on a lift and moved the transaxle back as far as it would go. It is a job but I got it down. Once the TT was out, the bearings looked OK, although it is hard to tell. I even spun the shaft up to idle RPM but couldn't tell. Anyway, I sourced out SKF bearings, then removed the inner and outer rubber and put them on the new bearings. The OEM bearings are hard to find and $$$$. All went back well so I had high hopes. Got it back in and took it to Chattanooga, and Charleston, SC for FCA events. The noise was still there, but maybe different. As you know by this time you are straining to hear anything! After concluding that the only other two things that turned in park or while not moving were the TC (torque converter) and whatever kind of pump they were using in the trans, I decided to pull it down. I bought a 1 ton engine lift (cherry picker) from Harbor Freight and used the base and cylinder to fashion a transaxle jack. That thing is VERY heavy so you have to have something. I did the same as last summer: remove bumper, oil cooler, half-shafts, wires, shift cable and slid it back. I pulled the TT down to recheck it. You also have to remove most of the exhaust. After some more work I got the transaxle down on my homemade jack. The next big job was getting the TC out. The ring nut is left-hand threaded and has factory red loctite so it was a bear to get off. I ended up having to make a socket with 4 tabs (picture attached), then make a bracket to hold the socket. I heated it some, but more heating may have broken it better. I hoped again to find something obvious like the flex plate being loose or cracked, but it was all perfect. The two "nose" bearings at the front of the housing behind the nut looked OK too, although my heating and beating on the ring nut did them in; I was going to replace them anyway and they were an easy match. I sent the (44lb!!!) TC to Ron (the owner) at Gene Browns transmissions in Houston, TX. I had read about him and seen some of his work. I talked to him on the phone first and was satisfied that he knew what to do. After some anxious days passed he called me. He said the old plate (looks like an old asbestos clutch or lock-up plate) was coming apart and would probably be making a shuttering noise or a rattle. I was never so happy to find out about a problem! He said the technology had improved a lot over the last 20 years and he would put in all seals, springs, bearings, and a new kevlar plate. He also said it was very out-of-balance; could have been Ferrari just using off the shelf GM TC parts, or it may have been dropped in shipping down there - and that he would rebalance it. I approved happily of the repairs (around $500 - a deal I thought after all that). As I waited on it to be returned I decided to dig a little more into this mysterious transmission that scares people. It is indeed very similar to a 4T80E. I replaced the solenoids: the 2 shift ones are in the bottom, and the TCC and pressure solenoids are under the back cover with the main filter (picture attached). All 4 of these are GM/Delco units, as well as the 3 filters - the main one in the back and the two "scavenger" ones in the pan. The fluid pump is also under the rear cover and it appears to be GM also (picture attached). The old unit seems pretty robust. I also replaced the two transaxle mounts that sink over time like the front motor mounts. I put it all back together and the car runs and shifts great. And best of all, all of the noise is gone. So here is my two cents worth: if you have a noise and take it to a shop, I would replace the TT bearings, pull the autotrans down (which they will probably end up doing anyway) and correctly fix it. Put the two bearings in the front of the housing, send the TC to Ron in Texas, and replace the 3 filters and 4 solenoids. Put one quart of Mobile full syn ATF in the TC and about 11 or 12 more in the transmission. For a little extra time and money (while you are in there), you will have covered all the bases, have an updated, balanced TC, and have a fully serviced trans. I am not a professional mechanic and this is not my day job - this is just intended to be info to help. Then to really make it a great car get the cats out, switch out the rear exhaust cans, bypass the immobilizer, send the window mechanisms to F1 in Florida, put in updated 575 motor mounts, put in a 34R redtop on a tender, etc........
     
  11. G. Pepper

    G. Pepper Three Time F1 World Champ
    Rossa Subscribed

    Mar 15, 2012
    33,723
    Texas/Colorado
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    George Pepper
    Outstanding post.

    What vehicles was that transmission used in? Many years ago I heard there were many similarities to the transmission in the HD GM pickups of the time, and that it was chosen because it could handle the V12 torque.
     
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  12. ChipM

    ChipM Rookie

    Jan 1, 2013
    40
    Spartanburg, SC
    Full Name:
    Chip McLeod
    1993 and up Allante, Seville STS, and Eldorado
     
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  13. chris_columbia

    chris_columbia Formula Junior
    Silver Subscribed

    Feb 5, 2008
    814
    Columbia MD
    Full Name:
    Chris
    Thanks Chip for spending so much time writing that post. I do indeed have a very similar noise, that at first I thought was a heat shield. Sometimes it's there, sometimes not...and it is coming fron TT/TC area.
     
  14. jcbam

    jcbam Karting

    Nov 30, 2019
    79
    New York
    first of all, thanks @ChipM for such a detail post. My GTA has the same rattling noise.
    @chris_columbia , did you end up fixed the TC problem like @ChipM described?
    I am trying to learn from everyone who has done this job so I can better manage the scope of the project.
    Thanks.
     
  15. chris_columbia

    chris_columbia Formula Junior
    Silver Subscribed

    Feb 5, 2008
    814
    Columbia MD
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    Chris
    No, I never fixed or looked into. Sold car in 2018, but on the look out for a replacement: GT or GTA.
     
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  16. WMW 700

    WMW 700 Rookie

    May 21, 2018
    33
    Norwich - UK
    Full Name:
    William Mark Wilkinson
    Hi, Did you ever fix your torque tube rattle?

    I replaced all the bearings in my tube about 4,000 miles ago and now its rattling again....

    Like yourself just trying to scope the job and find specialist company in the UK who will permanently take my annoyance away
     
  17. jcbam

    jcbam Karting

    Nov 30, 2019
    79
    New York

    I plan to replace the 3 TT bearings in the coming winters and remove the TC for rebuild. So far I tend to believe in @ChipM the rattling is coming to the TC. I went underneath the car with the engine on and traced the rattling noise and the TC seemed to be the source of rattling. Let me know how it goes with your situation.
     
  18. WMW 700

    WMW 700 Rookie

    May 21, 2018
    33
    Norwich - UK
    Full Name:
    William Mark Wilkinson
    Like you I do tend to agree with @ChipM and the work he did certainly sorted his rattle out. The Ferrari bearings for the torque tube shaft are horrendously expensive even avoiding purchasing them directly from Ferrari dealer. I've been looking to see if anybody can replicate the external rubber moulding as the bearings are pretty standard issue and cheap as chips here in the UK. Unfortunately with set up costs the company I approached wasn't prepared to progress my request given I only needed 3 pieces. I'm sure across the Ferrari community particualrly in the USA there must be someone who has improved the original NVH design of the outer rubber fitment attached to the bearing.

    I'm not planning to do the Torque Tube rattle this year as wallet is still recovering from a full valve guide overhaul in 2019
     
  19. henryr

    henryr Two Time F1 World Champ
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    Nov 10, 2003
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    Atlanta
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    Juan Sánchez Villa-L
    whatever happened to franklin?
     
  20. WMW 700

    WMW 700 Rookie

    May 21, 2018
    33
    Norwich - UK
    Full Name:
    William Mark Wilkinson
    Not sure what you mean by what happened to franklin.......think you may have wrong person
     
  21. Auraraptor

    Auraraptor F1 World Champ
    Lifetime Rossa Owner

    Sep 25, 2002
    13,197
    MO
    I always wanted to do a auto > DCT swap using one of the modern DCTs with an independent controller. A modern DCT would be a perfect compliment and fix my only issue with the 456.
     
  22. henryr

    henryr Two Time F1 World Champ
    Silver Subscribed

    Nov 10, 2003
    21,653
    Atlanta
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    Juan Sánchez Villa-L
    the original poster.... franklin parker
     
  23. ChipM

    ChipM Rookie

    Jan 1, 2013
    40
    Spartanburg, SC
    Full Name:
    Chip McLeod
    Hello, been a long time. I will post this in the two threads, 456GTA Transmission and 456 Auto Tranny. I (Chip) posted a lot in 2017 on all my 456 issues. I haven't since then but recently a few folks have reached out to me for updates. This is not my day job and nothing to gain, but I love working on cars and sharing info that may help. I am still the South Carolina (US) Chapter President for the Ferrari Club so I still talk to people all over the place about 456s. Anyway - If you go back you will see I replaced the bearings twice and had the TT down 3 times trying to find this rattle. I then ended up having the TC rebuilt. It did help the noise and rattle but did NOT stop it all. It may help others but a word of caution before you dig into this very difficult task of removal and rebuilding the torque converter that it may make you feel good long term to have a new one (with updated internals, etc) but it did not remove all of the rattles. Since those posts I have pulled the TT down once again. The bearings look good and only have 2000 miles on them. I have worked on cars and built engines all my life from Ford flat heads up to this 456 and a 348 but to me (as an old farm boy) bearings don't rattle much unless there are big issues. I took the rubber off the originals, matched up the bearings using measurements and epoxied the rubber back on. All that still looks good. Again, do all this with your own due diligence but this info may help you make decisions. I have now had the chance to spend time around 3 other auto GTAs (2 M's and one other GTA) and they ALL make the exact same noises. I have pretty much resigned myself to just live with it unless I am missing something easy. I had a really interesting conversation about a year ago though that I thought I would share. I ended up talking to a Ferrari old-timer that had detailed knowledge of working on 456s when new. He told me that they were supposed to be "balanced" before left left the factory but it was seldom done or done correctly. This would just be on the autos since the manuals would not have the shafts turning in neutral or with the clutch depressed. He said there were plugs that were supposed to go into small holes in the flywheel of the autos, and the manual flywheels do not have the holes. If you look on the diagrams you will see them and a part number for them. The diagrams are unfortunately harder to find but EuroSpares still has them up. I took the small inspection cover (with the holes in it) off the bottom of mine and I see these holes. There are no plugs in there. I have no idea if there ever was, or they were rubber and rotted up, etc. I would love to see one of the plugs but then I would have not idea if every hole had one or if they were truly balanced somehow when new. Very interesting though. I don't have any intention of doing any more TT removal unless the noise gets a lot worse or a bearing is truly having issues. I have someone wanting to buy my car so I am thinking about selling it and getting a 612 or FF. My last project, hopefully, I will finish before that is putting in one of the SRI/Helms fuse boxes and new connectors. My car will require the right buyer since the cats are gone and the airbags long since gone too. Hope all this helps someone weigh out expensive decisions.
     
  24. WMW 700

    WMW 700 Rookie

    May 21, 2018
    33
    Norwich - UK
    Full Name:
    William Mark Wilkinson
    Chip,

    Many thanks for the detailed overview of your experiences trying to irradicate the "infamous" rattle from the torque tube. Several years ago when I embarked on the TT rattle adventure, I too discovered all the flywheel weights were sitting in the bottom of the housing. It appears the weights were simply glued into the flywheel and of course with time, the glue goes off, and hence they fall out. Having replaced all the weights and rebalanced the flywheel the rattle remained although much reduced.

    Balancing is generally the source of vibration issues and there are a number of sources on the 456M GTA which could be the source or collectively contributing to the overall level that creates the rattle. I guess its just a case of working through them until it disappears.

    Unfortunately, I never got a reply from the US transmission specialist who opened up the torque converter and discovered a number of issues related to GM fitted components. I asked if he could provide a list of the parts he replaced but I guess that was a request too far coming from someone out of the USA.

    Like you I may have to live with the rattle if I can't find a specialist here in the UK to support me in my quest.

    Kind regards

    Mark
     

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