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Discussion Starter #1
Has anyone ever tried to figure out the odds or percentage of broken transmissions?

Maybe we can all post in here with a short reason as to why or what you were doing when it broke, and get some kind of idea of just how bad or good these transmissions are...
 

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This was probably number two on my bucket list after I got mine.

So much so, I went and bought a Holloway (Derek Bell variant) UN1 upgrade kit with the thought the UN1 was one step away from breaking. I since discovered as long as you don't drive it like you stole it and don't hammer it from a dead start, don't try speed shifting, and be careful hard accelerating on uneven surfaces, ie, don't drive like a maniac, the UN1 is good (assuming it's been treated same by previous owners, which evidently mine was). So, I sold the upgrade and haven't looked back... Mostly... I do like the idea of a closer ratio gear set, which was a secondary inducement for the upgrade

Hope this helps
 

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Discussion Starter #3
That's quite a list of things "not to do" with a $100k car. I want to accelerate hard. I want to be able to launch every now and again from a stop. I want to know I can shift quickly without breaking my tranny on stock power. And mostly, I want piece of mind.

Maybe I picked the wrong chassis?
 

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Mine was somewhat screwed when I bought the car, presumably from some harsh treatment in a previous life. 13 year old car had only ~23K miles when I bought it last year. Second gear synchro not working (double clutching required), some clutch drag at rest.

Clutch, pilot, throwout?, and clutch slave cylinder replaced. GTO upgrade kit, new synchro, and Quaife LSD installed. A few issues getting it all together and installed.

All good now at ~31K miles. Removing cash from the wallet 'adds lightness'. :bow:

Stu
 

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i've yet to really dump the clutch, or launch really hard from a stop. I have shifted pretty quickly and it does it just fine. I just dont let the clutch out super fast. I've accelerated real hard once in second but havent ever gone wide open in first. It definately doesnt have any issue roasting the rock hard tires. Im sure with some fresh sticky tires it wont be quiet as happy and will wheel hop. I not really scared of it breaking, but definitely dont want to promote it. However im like you and have to enjoy driving the car not just staring at it. Id imagine wheel hop is the killer like in all cars. Im sure in most cases when modded it's not necessarily a shaft just shearing from so much power, more so over fatigued with wheel hop and the differential deflection in the transmission casing that causes the breakage. Keep in mind clutches are a wear item made to be worn vs driveline shock. Drive how you want to but lift if your not just spinning normally and are hopping or bouncing on an uneven surface. Considering the age of all the esprits any worn out bushings or shocks will make wheel hop occur more easily.
 

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I've had PLENTY of fun with my Esprit, never once dumping the clutch at a light. You can have tons of fun with an Esprit without having to drive it like a ham-fisted moron, you just have to learn the car...
 

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If you flog the car you can expect parts to fail. On the Esprit it can happen sooner than on some other cars but there is always something that is going to break on any car. If dumping the clutch is what you want get something else that is cheaper to fix. The UN-1 can last a long time but not if you abuse it regularly. The Lotus is not a dragster.
David Teitelbaum
 

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Discussion Starter #8
No one said anything about dumping a clutch or drag racing. You're insinuating that launching the car at all will result in catastrophic failure. Launching and clutch dumping are two different things.
 

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I think it all depends on what you are expecting and comparing it to.

I haven't had any problems with my V8's transmission at all, in fact I was pleasantly surprised that it wasn't nearly as bad as folks seem to make it out to be. It shifts pretty smoothly, and has a much better feel than the DeLorean that uses the same UN1 box.

For all the doom and gloom that I heard about them failing, it doesn't seem to come up on the forums much at all that someone killed their tranny. I expected it to be a regular post topic, but it never is.

As someone else said, don't expect a dragster, but of course some "spirited" driving is to be expected. The way I see it, if it breaks, it's a good excuse to go with the upgraded "Bell" kit.

However, if you know you will be tracking the car, modifying it with a lot more power, or drive it in muscle car fashion, you might want to go with the upgrade from the start.
 

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Discussion Starter #10
I agree with that ^^^


I guess if it's as common as I heard, the threads would be plentiful with info. I got my esprit on Friday and I've went through a tank of gas already. I love it.
 

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I agree with that ^^^


I guess if it's as common as I heard, the threads would be plentiful with info. I got my esprit on Friday and I've went through a tank of gas already. I love it.
Yes, I think it's been overblown a bit. Glad you are enjoying the car! :D
 

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2nd gear syncros ARE a weak spot on the Renault transmissions IIRC.

I should talk, though. Two (Citroen) tranny rebuilds over 15 years....practice makes perfect, I guess.

:sad:
 

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Discussion Starter #13
I've read to be careful accelerating in first and the first to second shift. Also, not to shift hard between any gear change.

This past weekend, I don't think I was below 5k at any point. I enjoyed that car. It's what I bought it for...
 

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I've read to be careful accelerating in first and the first to second shift. Also, not to shift hard between any gear change.

This past weekend, I don't think I was below 5k at any point. I enjoyed that car. It's what I bought it for...
When Lotus was doing warranty work and found teeth removed from the crown gear they do a dump of the ECU to see how the car was driven. Guess how they honored the warranty if they found out about the multiple standing starts? Shock loads are deadly and happen mainly under 2 conditions. The first is dumping the clutch while redlining the motor in first while not moving. The other way is if a wheel starts spinning and suddenly catches. The spinning is very bad for the spider gears and the suddenly catching rips the teeth on the crown wheel. No car can take constant abuse and survive. Some can take more of it than others. Dragsters and race cars get torn down and have parts replaced regularly before they fail. Not usually done in a street car. 2-3, 3-4 and 4-5 upshifts are not as bad on the transmission and just results in premature wear on the syncros. The Lotus was not meant to out HP other cars, it excels in handling and that is where the finesse of a driver can make all the difference.
David Teitelbaum
 

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Just look at the size of the gears and the crown wheel and spider gears in the differential, there's your answer. The transaxle will handle just over 400 foot pounds of torque if applied rationally. I track my 2000 Esprit about once a year, but I track it as a sports car not a drag racer.
 

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Some folks who know a lot about this subject are the GT40 guys running UN1s behind small block fords, all of which are making 400+ hp/tq.

The bottom line is that not a lot of these are breaking. Considering how much more hp/tq is being put through a UNI compared to its design spec it's surprising...and a testiment to the robustness of the transaxle.

Not acting like a 16 year old idiot behind the wheel certainly improves the longevity. Drop clutch burn outs and similar undertakings are going to take a toll...on any transaxle, not just what's in a Lotus.

If you like to beat up on your gear box/transaxle then you're probably better off with a corvette. A ferrari transaxle won't take a beating for long, and neither will a porsche.

Have some respect for the machinery and things will work out a lot better for you.
 
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