Anybody done a CVT to manual swap?

Discussion in 'Honda Hybrids' started by pasadena_commut, Sep 21, 2010.

  1. pasadena_commut

    pasadena_commut Well-Known Member

    Given the CVT's proclivity for failing expensively I wonder if anybody has done a CVT to manual transmission swap on an HCH I? Tried to find info to that effect with google, but the keywords were too common. I'm guessing one can pick up a used manual for something around $1000, plus maybe another couple of hundred for the clutch pedal and other bits of hardware. Anybody know what it would cost, ballpark, to install it?

    The reason I'm asking...

    Our 2003 HCHI is going into the shop for judder today. I looked back through the service records (the original owner kept everything) and it has been around 8K miles since the last CVT fluid change (about 2K miles before I bought it, at which point there was no judder), and there was another about 8K miles before that, complete with a dual flush of the CVT fluid. Seems like a transmission that can't stay judder free for more than a year or 8K miles is probably not all that long for the world. Also it has had several episodes where pulling away from a stop it rev'd up like it was in a low gear or a clutch was slipping. So I'm exploring my options for when this turd of a transmission can no longer be kept running by Honda's bubble gum and bailing wire service methods.
  2. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    I don't know what differences in ECU might be needed...
  3. pasadena_commut

    pasadena_commut Well-Known Member

    Have not yet heard back from them yet, fearing the worst. (It's a dealer right?)

    If/when they do try to sell me a replacement CVT, can somebody tell me if the CVT replacements Honda dealers are installing are the same as in the 2005 HCHI (which seems to have had fewer transmission problems than the 2003). Or are they replacing broken 2003 CVTs with soon to be broken unchanged 2003 type CVTs?

    For that matter, isn't the more complex fix described in the 07-049 or 07-050 TSB a replacement of the starter clutch and not the entire transmission? I had one of those "cover your wallet" moments when one of the first things the fellow at the desk told me was that they don't fix CVTs, just replace them. The car is well under the 105K mile limit, but I bet they will find that it is, sorry, 6 months past the 7 year extension. (Courtesy of several short interval CVT fluid changes by the previous owner's Honda dealer.)

    Last edited: Sep 21, 2010
  4. msantos

    msantos Eco Accelerometrist

    Hi Pasadena;

    Correct. Depending on the circumstances and the level of technical qualifications at a given Honda dealer, corporate Honda will often choose a complete CVT replacement rather than a mere parts replacement. Let's just say that there not all dealers are alike and these decisions are made on the basis of potential success and established dealer competency.

    If I recall correctly, I have seen 2003 and 2004 models hosting 2005 CVT transmissions replacements with very good results. It is a little costly though since that usually involves the replacement of other components too... but in my view, it is still cheaper and much, much easier that contemplating replacing the CVT with the OEM 5MT transmission. ;)


  5. pasadena_commut

    pasadena_commut Well-Known Member

    Information which is, of course, not available to the customer, except perhaps anecdotally, through yelp and the like, or word of mouth. (Not an unusual situation, picking doctors is often the same deal.)

    Ah well. In this instance the system seems to be working. The service folks said the car will be covered under the TSB's extended warranty. Not quite sure yet which repair they are planning, since the paperwork refers somewhat confusingly to "special order valve assy (service bulletin:07-049/050)". It will take a few days before the parts come in.

    I'll keep that option in mind, if it becomes necessary. What did they change for the later HCHI CVTs that made them more reliable than the 2003 version? Is the 2005 a modified version of the 2003 with a few parts beefed up, or is it a different transmission in the same form factor?

  6. msirach

    msirach Well-Known Member

    Glad to see you got a positive response! Good Luck!
  7. msantos

    msantos Eco Accelerometrist

    Yes, and no. Yes, while the information you seek is not plastered anywhere in explicit terms, there's much customers can do to narrow their selection. For instance, while experience is a definite asset on the part of the technicians doing the job, that alone is not anymore a guarantee of success when diagnosing and servicing advanced hybrid platforms. In fact, the single biggest determinant of success is certification and training.

    That is why we recommend owners/customers ask their service advisor how many of their technicians have been certified and when? If they have a good number of them, then the chances of greater competency work being done on your vehicle are very good. Asking different dealers this same question should help identify those that are less able to deliver in terms of expediency and quality.

    You can also ask your local BBB for an idea of the relative number of complaints leveraged against a given service department. Looking into the dealer's service lot also helps especially if you see a good number of hybrid that are in for regular maintenance/servicing.... and so on.

    As far as design goes, the transmissions are (on the surface), identical in almost every visible detail. However, since the most critical components on the later revisions were manufactured in-house, the manufacturing and component specifications have changed (for the better). That is why today's CVT's present on the HCH-II (also manufactured in-house) are base-lining better than some of the more traditional 5 speed automatic transmission Honda offers in some of their non-hybrid vehicles. ;)


  8. PaleMelanesian

    PaleMelanesian Beat the System Staff Member


    Ours was replaced under warranty when it went in for an oil change and failed to reverse out of the service bay.
  9. pasadena_commut

    pasadena_commut Well-Known Member


    It was hard to tell from the 07-049 TSB, but is the start clutch in the CVT actually immersed in the CVT fluid, or is it in a separate compartment within the CVT housing? If the former, maybe it's just me, but that doesn't seem like such a great idea. Regular automatic transmissions have internal clutches swimming in fluid, but they need not be large because the torque converter handles the role analogous to that of a manual transmission clutch. If for the CVT they put a mechanism which is a lot closer in function to a regular manual transmission clutch inside the transmission then it opens up Pandora's box: who knows what evil chemistry will take place when the CVT fluid contacts the hot clutch plates, and the inevitable clutch plate wear products and heat will end up circulating in the transmission.
  10. MaxxMPG

    MaxxMPG Hasta Lavista AAA-Vee Von't Be Bach

    Clutch packs and other rotating parts are not submerged in fluid. In fact, overfilling an automatic transmission becomes dangerous (to the transmission) because doing so does submerge moving parts in the fluid. This leads to the fluid churning and foaming into a froth. And since air is compressible while liquid is not, the air/fluid froth leads to serious slippage and poor lubrication, and subsequent component failure.

    The clutch packs are not harmed by the fluid. In fact, the fluid is pumped into the clutch drum under pressure to overcome the release springs and press the plates together with enough force to allow friction between the alternating metal and composite plates to permit the transfer of engine force between the two sets of plates.

    Also, heat buildup is due to friction, and the clutch packs shouldn't get too warm from friction if they are applying properly. When the clutches are worn, or fluid level is low, or the incorrect fluid is used, or the charge pump (or pressure control) is out of spec, slippage will result and that leads to rapid heat buildup and degradation of the fluid.

    While I am no IMA CVT guru, it is entirely possible to have the "older" and "newer" units appear identical in parts diagrams, and even function in an identical manner. In these instances (based on cases involving other transmissions), the secret is in the part numbers, where the upgraded versions use components that are visibly identical, but have significant differences in their properties due to changes in metallurgy or slightly different tolerances.

    Here is a pdf of the CVT parts list. It shows you a drawing of the parts that are "inside the box", so you can get an idea of how it all fits together.
    Note that the drawings are oriented that the "back" of the transmission (surface farthest from the engine) is facing up.
  11. jmelson

    jmelson Well-Known Member

    This is much like a motorcycle transmission, where the clutch runs in an oil bath.
    Most fixed-gear automatic transmissions also use such multiplate oil-pack clutches, but use them mostly in an on/off mode, where the engagement is done pretty quickly. The motorcycles use them as the manual clutch to get the vehicle started rolling, like the Honda CVT. The computer manages the clutch engagement by adjusting pressure on the clutch pack as well as modulating engine and IMA output to get something approaching a smooth start. It is really noticeable when backing up an incline, I could do much better with a typical dry-plate car clutch.

  12. Gairwyn

    Gairwyn think green

    From the sounds of the part they've ordered, it seems to be the one mentioned in TSB 07-050, the CVT lower valve body replacement:

    when I had mine worked on they ordered the start clutch kit, which seems to go more with TSB 07-049:

    I figured I'd put both of those links in here in case they might help with your questions about the location of the start clutch, etcetera.

    I've often wondered if the reason the 2003 and 2004 CVTs had more problems is because they originally had the ATF-Z1 trans fluid in them, and Honda later switched over to the CVT trans fluid. The original fluid was found to be harming the CVT. I have always wondered if the parts were the same or not. I also wonder if the replacement parts are used/remanufactured or newly-made. I'm thinking remanufactured.
  13. pasadena_commut

    pasadena_commut Well-Known Member

    Still waiting on the part to arrive but, yes, I think it is the valve body. The diagnostic for 049 is (in a nutshell) "is there judder" whereas the one for 050 is "does the motor spin too fast". Well, my car definitely has judder. However, it also has instances where the motor spins too fast, WAY too fast, but that has been only a handful of episodes over a year, and the rest of the time the RPMs are as they should be. The over rev seems more like a software glitch than anything else, since power cycling the car fixes it. I dread that it might happen some day in heavy traffic, facing uphill, on a road with no shoulders...
  14. pasadena_commut

    pasadena_commut Well-Known Member

    Still STILL waiting, 9 days and counting. Is that typical???

    By the way, mechanically, how does the CVT work when the car is stopped, but not autostopped? There is no torque converter to uncouple the motor from the transmission at low RPMs. Does the CVT open the start clutch (as if on a manual) or does it shift into neutral (to avoid wearing the clutch)?
  15. jmelson

    jmelson Well-Known Member

    That's why this is called the "start clutch", it is used to start the vehicle from standstill. At idle, they lower the hydraulic pressure on the clutch pack very close to zero, and basically all you have is fluid drag on the plates. There really IS no neutral on this transmission, I think, they just lower the start clutch pressure all the way to zero.

  16. pasadena_commut

    pasadena_commut Well-Known Member

  17. Gairwyn

    Gairwyn think green

    Yeah, I noticed that today when I was reading at another forum.

    Still waiting for your part to come in?
  18. pasadena_commut

    pasadena_commut Well-Known Member

    Funny you should ask...

    I kept calling them and getting the run around, "so and so isn't in today", "we don't have any record of the part being ordered", and finally one of the service people went back into the parts department and (I am told) "found the part on a shelf without a ticket attached to it". So I brought the car in today to have it installed and then they call me up and ask if it has ever been burnished, because "that fixes it".


    Now they are back pedaling furiously on fixing it under the TSB, which they said in no uncertain terms the first time I was in that they would do. And they must have ordered the part to do so, since it eventually showed up, even though they now have no record of how that happened. They now say the 7 year TSB deadline passed a couple of months ago, which if true, they certainly must have been able to determine at the first service visit. Now they want to contact the Honda dealer that used to service it for the previous owner, for what I'm not entirely sure. That dealer changed the CVT fluid every 8-10K miles for the last few years with no specific comments as to why. Well, there was a comment about fluid contamination and two CVT flushes (but nothing about burnishing) from 2007, but that doesn't explain the later increased rate of CVT fluid changes.

    All hope is not yet lost, but this is the sort of CVT related nonsense I was hoping to at least avoid in future by putting in a manual transmission. Not that manual transmissions don't break sometimes too, but at least those you can take to any number of transmission shops. Also they don't need constant refills of exotic and expensive fluids.
  19. pasadena_commut

    pasadena_commut Well-Known Member

    The saga continues.

    They did the burnishing procedure yesterday and now it doesn't judder anymore. I picked it up since they are "still talking to Honda" and wouldn't be doing anything to it until that is resolved. There is a slight vibration at the same point where the judder used to be that I don't remember, but then it has been a long long time with the judder, so maybe I just forgot what the transmission felt like without it. Apparently they didn't do the burnish the first time in, which is messed up for two reasons. First, the TSB requires that it be done before going on to replacing the start clutch, so either they didn't do the TSB diagnostic properly or they did and didn't report it to me. Second, from what I have read a burnish procedure will resuscitate a bad start clutch for a few thousand miles unless it is completely toast. Counting yesterday's burnishing, the car is now averaging one complete CVT fluid change about every 6K miles over the last 20K miles (most of which took place before I bought it). This is clearly not normal - no working transmission needs fluid changes at the same frequency as motor oil changes! (Coincidentally, I will only drive this car about 6K miles per year.)

    When I first took the car in to this dealer I brought copies of the service records from the previous honda dealers it had visited. Of course they lost them. So I just gave them another set.

    Did the burnish "fix" the transmission permanently? I doubt it. Future fun arguing with Honda seems pretty much inevitable at this point.
  20. polygaryd

    polygaryd New Member

    I am currently in the middle of the cvt to manual swap in an hch (Honda civic hybrid). I have a complete running manual hch and a running but unable to move (of course) automatic hch. the donor car has really high miles and is all beat up but runs excellent and the auto is in really nice shape with low miles for the year with a brand new battery.

    All I can say about this swap is it SUCKS big time and I will never attempt this again. I am not a novice when it comes to transmission swaps from 3 speed auto to 4 speed auto or auto to manual. This is a nightmare. Usually it takes about a day to do a swap right with even the correct interior, its been 3 days now (10 to 12 hour days) and still not done.

    The harness inside the car and engine harness need to be swapped, the ecm(which requires the dash to be removed(the bolted it in from the back side/firewall side WTF)). the intake has to come off just to get to the 3 sensors under it to remove the harness. The subframe must come down (even to do a clutch replacement) which is ridiculous imo. There is however a plate covering the hole for the clutch master cylinder and can be drilled through easily BUT!!!!!! there is no top bolt hole for the clutch pedal to thread into (they spot weld one in the manual cars OMG and FML but seriously WTF and what to do?). The front trans mount (by the radiator) is different as well as the bracket that goes on top of the trans that holds the air box. The bolts are different lengths for the auto shifter and the manual shifter. the shifter linkage runs up the same spot as the auto and uses the same bolts under the car to hold it in in the same spot also. I haven't done the interior wiring or gauge cluster yet so I will post back when I have completed this probably tomorrow. still have to get the trans in, subframe up, suspension hooked up, and wheels on or HOA will fine me by tomorrow at 8am.. HOA's suck also btw whoever came up with them should be shot, nothing but a head ache on top of this mess of a swap

    PS. If you want to do the rear main seal (rear crank oil seal), you have to take the ima rotor off, Honda wants ~$500 for the tool and takes weeks to get all to replace a 14 dollar seal. I always do the rear main seal when the trans is down, no matter what vehicle its in or mileage. To get around buying the tool and almost never using it maybe never using it again, I improvised. I wrapped the ima rotor with thick glossed crad stock(i didnt have the plastic they use at the dealer) it fits in between the rotor and stator to not damage the stator magnets. I then rented an ac clutch puller, and took off the hooks, used two of the three rear trans motor mount bolts(from subframe to mount NOT from mount to trans) they are long with the same thread pitch. You need to get a longer bolt to use in the a/c puller but that wont cost you but a few bucks vs $500 then pull the ima rotor, replace the seal carefully by not scoring the crank when your hammering the seal with a screwdriver to get it out. Replace and the use the puller to slowly allow the ima rotor to retract into the stator area against the crank. DO NOT USE YOUR HANDS TO DO THIS IT CAN TAKE YOUR FINGERS OFF. Return the rental tools to autozone and get all your money back final cost 14 dollars (unless you have to buy the bolt i mentioned( I had one)).

    I hope this has helped at least someone either know what your in for or to decide to sell the pos automatic and get a stick car, aka, screw the swap.

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