Looking for a new/used gearbox or internals .. or someone interested in a project - 2011 S

[TomE]

Sadly my 2011 Evora S has been diagnosed with a gearbox issue.  It is probably a chipped tooth on 1st and/or 2nd but may also be some wear on other parts.  The only way to be sure is to take the gearbox out and either replace the whole thing or open it up and do some major surgery.  In addition, although the clutch is engaging fine, the throw-out bearing noise has got gradually worse and if the gearbox is coming out I may as well do the clutch at the same time.

The 400 clutch kits are available from Lotus.  But many of the gearbox internals are out of stock and with no timeframe for re-orders.  I'm therefore looking for any gearbox parts or a whole gearbox that might be available.  That could be a used gearbox if the history is known.

For background, the car has only done 28,000 miles (I know, I should get out more - but have other fun cars too).  I bought it when it was 9 months old and it had some slight transmission and release bearing noise then.  Lotus field service looked at it at 1 and 3 years old and agreed it was slightly noisier than other Evoras but not anything to worry about.  The car had the replacement shifter cables and master cylinder while still under warranty, changed over to uprated gearbox oil and has run smoothly and faultlessly for 10+ years apart from the noise.  Early last year it seemed like the release bearing noise was louder and more obvious in 1st, 2nd and 3rd.  B&C reviewed it again - no issues found but now described as one of the noisier cars they'd heard.

In November it started developing an odd lurch or hesitation when engaging the clutch in 1st and 2nd, so Back on Track and B&C had the car for road tests and investigations.  That resulted in a replacement clutch sensor, which cured the lurch, but the more detailed investigations revealed the problem with the gearbox as well as the noisy clutch.  Both have said it's now one of the noisiest they've heard.

As I've been waiting for an Emira, this was happening in parallel with the Emira test drives and checkout process.  Prior to the diagnosis, I'd been planning on keeping the Evora when the Emira arrived, as they are different propositions and the Evora has been a big part of our family and the children growing up with it.  I've now decided to postpone my Emira order by at least 12 months (a long and complicated story) but have left my deposits in place and will take a view once Base Edition info is released.

In the meantime I would like to repair the Evora and probably keep it.  But if I can't sort source a gearbox or internals and someone is interested in taking on the car as a project then get in touch.

[Rambo]

I'm sure I read of another Evora S owner having gearbox issues recently.

[jerzybondov]

I thought legend had it that it’s 4th gear that is the one to watch out for?

Sorry to hear about these developments Tom l, especially at such low mileage. The transmission noise (particularly noticeable at low revs under load) is common to all Evoras isn’t it? This is the noise you’re referring to being a bit louder than it should?

What makes B&C think it’s first and second gears that are on the blink? These are the Aisin originals aren’t they, rather than the shorter higher gears which Lotus put in?

Sorry - lots of questions!

Edited January 21, 2023 by jerzybondov

[Philsport300]

South West Lotus rebuild the gearbox and shim it correctly, something Lotus don't do. The result is that the transmission whine is gone

[TomE]

1 hour ago, Rambo said:

I'm sure I read of another Evora S owner having gearbox issues recently.

Good point, Phil Peek was asking about one on SELOC and Pierre put him in touch with someone.  @series_onenot sure if you know of any others?

[Whitey]

Sorry to hear about your gearbox troubles Tom, and Emira delay. I thought jubu or MWR did replacement and updated internals? Could also try ES and Steve Williams as they race Evoras. Last thought is Alan Voigts who specialise in rebuilding gearboxes. Good luck for swift fix and hopefully it will be better than when new.

[TomE]

2 minutes ago, jerzybondov said:

I thought legend had it that it’s 4th gear that is the one to watch out for?

Sorry to hear about these developments Tom l, especially at such low mileage. The transmission noise (particularly noticeable at low revs under load) is common to all Evoras isn’t it? This is the noise you’re referring to being a bit louder than it should?

What makes B&C think it’s first and second gears that are on the blink? These are the Aisin originals aren’t they, rather than the shorter higher gears which Lotus put in?

Sorry - lots of questions!

I've not been following threads about gearboxes until recently, it was only clutches I was keeping an eye on!  So I'm not sure which gears are more prone than others.  I've read recently of people who have lost 6th or 6th and 5th.  The worry is that if there's a sudden catastrophic failure then it can take out the casing as well, so then you can't refurbish the internals and have to replace the whole box.  It appears that replacement and refurbishment are going to cost similar amounts in total.

You're correct it's partly the low revs noise common to many Evoras, which I believe is down to the release bearing in the clutch.  But there is also a second type of noise at low speeds and as Phil says is initially due to poor shimming inside the gearbox and if it gets louder is probably some sort of wear.

Both Jez at BOT and Richard at B&C could feel a regular rotation-based unevenness when letting the car move forward at idle in first or second, which is what's suggesting a broken tooth.

[jep]

I'd definitely speak to Steve Williams, he seems to know Evora gearbox well and definitely raced them.

Justin 

[Rambo]

3 hours ago, TomE said:

Good point, Phil Peek was asking about one on SELOC and Pierre put him in touch with someone.  @series_onenot sure if you know of any others?

From memory, the S with gearbox problems was 5th/6th gears but I can't remember where I read it 🤔

[Bravo73]

I’d ask ES if they have any gearboxes sitting on their shelf. 

[DH2]

3 hours ago, TomE said:

a regular rotation-based unevenness when letting the car move forward at idle in first or second, which is what's suggesting a broken tooth.

If a tooth fails it tends to shred them, and would certainly make a hell of a noise.  More likely to be damage or play in the splines between gear and shaft - I've heard a few making a load of chatter in that scenario (as well as the usual clutch chattering).

We (H111) have certainly got a couple of boxes on the shelf, from memory, but they are upgraded, rather than standard.  I think we sold our last standard one.  We've extracted and rebuilt a fair number of them though, if that helps.

Dave

[TomE]

Thanks Dave, that makes sense and the mechanism of wear and play in the splines might explain why it's gradually got louder rather than been sudden like when something breaks.

I'm not familiar with upgrades that are possible on the gearbox, only the long and short ratio variants.  When you say you have upgraded ones but not standard, what are the main differences and would that be a route I could go with mine?

Thanks to everyone for the various suggestions so far, I'll be contacting a few people on Monday.

[LotusLeftLotusRight]

My GTE’s Evora S gearbox failed very early (<3000 miles). I heard and felt something break, when changing up whilst accelerating hard away from a roundabout.  I managed to limp home with the remaining gears. I booked it in to Lotus Silverstone and thankfully nursed it the 30 miles there. I took a technician out and we drove barely 1/2 mile before turning back, at which point there was a clunk and a box of neutrals. I somehow found a gear and we crawled back to the workshop. As we got out the technician noticed a telltale trail of transmission oil behind the car. Basically it seems that whatever had broken originally was rattling round inside and eventually shot itself through the gearbox casing, rendering it scrap. The gearbox was returned to Lotus for investigation, but I don’t know what they found out. JMG personally reviewed the case and agreed to supply a free of charge replacement gearbox, but I had to pay the labour cost. It actually turned out to be a positive for me, because the replacement gearbox was a genuine GTE development unit, which is still in the car today.

In my experience, you don’t want to risk this terminal damage by continuing to drive it.

[jep]

I certainly didn't drive my NA when I lost 3rd, 4th, 5th and 6th. I had to get to a safe location - a few miles and B&C collected. 

Definitely don't drive it - it's just not worth the risk to turn a problem in to a bigger problem. 

Justin

 

[DH2]

5 hours ago, TomE said:

Thanks Dave, that makes sense and the mechanism of wear and play in the splines might explain why it's gradually got louder rather than been sudden like when something breaks.

I'm not familiar with upgrades that are possible on the gearbox, only the long and short ratio variants.  When you say you have upgraded ones but not standard, what are the main differences and would that be a route I could go with mine?

Other than the weak gears on the earlier sport ratio boxes, the main problem with the box (and same on EC60 box on the 2ZR Elise) is the plastic shims on the selector forks. Toyota did move to fitting brass pads on one of the forks, and other suppliers have done similar.  We braze them with phosphor bronze on all selectors.  Oil cooler helps look after the selectors and synchros in general.  It depends on individual circumstances what works best - i.e. road vs track use, etc.

As stated above, continued use often makes a bigger mess inside, and more parts end up needing replacement.

Dave

 

[jerzybondov]

Is there a commonly understood point at which early (ie at risk) CR gearboxes became later (ie less risk) CR gearboxes?

[jep]

I understand sorted by the time Evora S was launched which was MY11. First S probably October or November 2010 (corrected typo). 

Justin

 

[DH2]

1 hour ago, jerzybondov said:

Is there a commonly understood point at which early (ie at risk) CR gearboxes became later (ie less risk) CR gearboxes?

VIN CH_10452 onwards.

[DH2]

42 minutes ago, jep said:

I understand sorted by the time Evora S was launched which was MY11. First S probably October or November 2011. 

VIN CH_10452 is actually MY12 (August 2011), car 0452 (serial number reset to 0001 at launch of MY12).

S was launched December 2010 with a BH VIN (MY11).

So there are S's out there with the weak gearset. We've replaced a few.

[jerzybondov]

Fantastically precise - thank you!

So let’s say you have a July 11 build Evora S… (like me 🙈) 

Anything you should do to mitigate risk?

For example, is it like the IMS bearing on a Porsche 996, where if they’re going to go pop they will do so by 30k-ish miles (and if they make it past that then they’ll be fine)? Or is it an inevitable mileage related degradation issue (like bore scoring on the same Porsche 996 🤣)

And if you are going to have an issue, what are the first warning signs?

I appreciate there may not be straight answers to any of these as the sample size is so small!

 

 

[jep]

@DH2 thanks. Typo in my post, corrected, but your precise info great. Sorry for confusing anyone. And news to me early S had gear issues on CR box. 

My CR box (2010 NA) lost 3,4,5,6 at 68000 miles. No warning signs at all. 

Justin 

[DH2]

44 minutes ago, jerzybondov said:

Anything you should do to mitigate risk?

Leave it in the garage.  Or not use the right pedal.  Or try not to worry about it too much. 😉

As stated earlier, I've heard them chatter on the shaft.  Or they just fail without notice.  In either case it's game over!

[IanA]

Lotus EA60 transmission (Aisin BG6)

I would re-build the box. All Toyota (Aisin)  parts except for 3,4,5,6 gears in Lotus Close ratio (Sport) gearset.

Below for info:

The faulty Lotus installed single CR 4/5 input gear in the Toyota EA60 was fixed in cars from mid 2012. The following may be useful in determining cars that are likely to be affected:

Lotus changed 3,4,5,6 gears for their Close Ratio or Sports box from VIN CHxxx10452 onwards to Lotus part no. B132xxx and in mid 2012 changed the specific 4/5th input gear identified as problematic from part no. B132F0047F to B132F0160F, which is used in current production Evoras and Exige V6's.

Change over to rectified Lotus parts was on mid MY12 cars. Sports Ratio (CR) Gearbox, from VIN CHxxx10452 onwards and Lotus inscribed Gear Box Serial no.GB1564 onwards.

The Lotus Gearbox Serial number (GBxxxx) containing Lotus CR gears is easily identified as is etched by Lotus onto both the transmission casing and the bell housing.

For re-build:

Main parts needed -
4/5 Input gear A132F0160F
4 Output gear B132F0051F
5 Output gear B132F0053F

Optional upgraded parts that were changed later (about 2016) to improve shifting -
Shift fork-No.1 (mod) S/Ratio A132F0349J
Plate-Interlock-modified (SR) A132F0220K
Gate-Gearshift (SR) A132F0206F

Note: CR, SR, S/Ratio, Sport, are Lotus Close Ratio gearset.

Aftermarket improvement for longevity for tracked cars -
Brass slipper pads for selector forks. The above No.1 shift fork is stronger and comes with brass slipper pads.

 

 

Edited January 22, 2023 by IanA
more info

[andyj007]

this issue of CR gearboxs failing was a desciding factor in offloading my 2010 N/A .. which   everytime i drove it i kept thinking it was going to go pop..  the combination of 6-7k to remove rebuild/ replace , new clutch whilst your in, but the  when not if scenario of  it failing leaving me strandard..    

the final nail in the coffin was speaking with a engineer manager  at lotus in person during  a factory  visit, who 'off the record' ( a few years have passed so im guessing its ok now) said the issue was with that their normal engineer suplier of lotus specific  ratio gearsets  could not keep up so they outsourced to another company and these were not hardened correctly..  ..  hence the when not if failure.  

FYI all the original lotus evora  press reports and road tests were carried out in CR ratio boxes,   it was/is a cracking set of ratios ..

OP coudl you not just get a replacement toyota gearbox , although this would be the long ratio version  ..  not as good  to drive IMO but pretty solid and available ..  

 

 

 

[IanA]

Toyota Avensis in the UK had the same ratios (long) with same FD pinion ratios as was supplied to Lotus, however the bell housing was relieved to relocate the starter motor by Lotus due rear engine application.

This is why I suggested that OP should re-build, unless he can locate a used Lotus one, which will likely need a re-build.

Edited February 14, 2023 by IanA
more info