With all of these posts about trannys grinding, it leads me to believe that the evo trans is built really poorly. I know a trans will grind due to syncro wear, but why? There are soo many posts about trannys being knotchy or grinding right out of the dealership with like 5 miles on it!! What gives, why does this happen. I know alot has to do with abuse, and launching. But why are they built soo poorly, what is the exact reason for the knotchyness, and grinding on really new cars? I know this has been discussed a thousand times, but it seems that the only answer people come up with are syncros, and to get it rebuilt by tre or shepard. Why does this happen, does anyone know??

 

Why was my thread moved, this is not a newbie question, this is more like a tech question. Thats not cool.

 

you are a newbie and it is a newbie question that can be answered by the search button which if you will research you will find out that the evo tranny is built strong to withstand the abuse and torture of newbie drivers. it can even withstand modded 4g63 up to a point which the audi A4 1.8t cannot take.

 

I dont think people are understanding my question! First off I am a newbie only because of my post counts. I know more then most people on this site. I know all about the power levels the trans can take. I know all about syncros, and gearing and what not. I have searched and no one knows why this happens, has nothing to do with abuse. Has to do with the design of the trans. Seems, a little too technical for most, anyone have any ideas what causes a brand new car to have grinding issues with 5 miles on the clock?

 

with my evo, the 1st 1000 miles the tranny was tight, hard to shift which i liked. as the mileage grew it became smooth almost no resistance when shifting. I miss the old feel but it wasn't any synchro issue. it is because it was new. if they are still complaining then they probably don't know how to shift properly. up to now, no issue at all. compared to my lexus IS300, the evo is every bit raw, raw power,raw tranny,loud and unforgiving but that's what keep us to like the evo even more.

 

I think it is a fair question. The first four years of DSMs that were made all had grinding tranny problems. My '92 started grinding 1st gear after a few hundred miles and it continued with every shift into first until the tranny died at about 70k. I bought a new replacement tranny from Mitsu and it wasn't much better even though I took special care with it.

You can tell right away that the Evo tranny is a much stouter unit but I still read of people having 1st gear grinding problems with MR's right off of the showroom floor. And I know Mitsu has been throwing money at the problem with double syncros and such. But still, they've known they had a problem for a long time with plenty of years to fix it but the problem continues.

Manual transmissions have been around since Adam. The proper design should have been figured out years ago.

 

I think there are alot of know it alls on this forum that can regurgitate the same BS over and over but have little general car knowlege. Theres really good people too but finding bs from non BS is hard.

I don't know that much about trannys but I think its mostly because people don't properly break in the tranny and try to slam it into gear all the time right when the car is new and they don't really know how to drive it yet. The engine has alot of power and it is easy to spin it up fast and miss gears and one incident can really screw stuff up. you have to shift carefully but once its in gear you can do whatever you want. It is supposed to have a notchy feel, thats no problem.

The other thing I would suspect as far as grinding in a brand new car is that clutch may need adjustment. I never had the grinding problem with mine.

 

shifting properly is one of the most overlooked ways to improve your times at the track, and it helps with the longevity of the drivetrain components too. If you can learn things such as rev matching and double clutching you will have the skills to use your vehicle properly in all situations, and you will notice that everything gets much smoother with your experience level.

Breaking a new vehicle in is very important as well. There are lot's of things in the manufacturing process that create burrs, sharp edges, rough spots, etc. that will wear out properly during a slow and proper break in period, and that can destroy your engine or drivetrain if you don't break your car in.

 

I'm sure it would have, except manufacturing processes, material tolerances, new alloys, etc. continue to evolve. When the first transmission was first developed no one even could begin to imagine a computer running and engine, or a turbo and forced induction. So no matter how long we are driving cars and developing more technology the only technology that could even become perfect would be outdated and useless compared to the new products with minor issues.

 

as far as I know the 5 spd evo tranny is pretty strong. Most of the broken stories I heard are from 6 spd.

 

....heavily modded 4g63 with 6 speed!

 

Synchro's themselves break in and the oil itself changes its vecosity properties as time wears on the parts.

Little do people realize that isn't horsepower that kills drivelines its torque.

Lets do a little experiement!



WK2 = Inertia of load to be accelerated lb-ft2

Weight of Object (W) lb = 3100lbs
Linear Velocity (V) fpm = 30mph or 2640fpm
Rotational Speed of shaft, (N) fpm = (in this case i'm going to use the tires so its equal to the linear velocity V) 2640fpm
Time to Accelerate (t) seconds= (Drop the clutch so a generous 1 second ) 1
Change in Speed () rpm = 5000rpm (Launch RPMS roughly )


Assuming your wheels STAY on the tarmac you would have put an astonishing 1274.7654 lbs of torque into your driveline.. Thats like throwing a boat at it. At 2seconds the inertia drops to 637 lbs...

 

The oldest car I've driven was a '49 Chevy. It was only a 3-speed but if you put something oily in the tranny you didn't have to double clutch, it didn't grind and it didn't matter how you threw it into gear. If this new technology has given us the notchy tranny Mitsu supplies somebody needs to send them a '49 Chevy tranny for study. The minor issue here is that some owners have to pull nearly new transmissions and send them to Shep to get them to work.

 

Your comment is totally absurd! You haven't heard many "broken histories" because there are only very very few 6 speeds that ever broke and that is because they raced it a lot and they also had a lot of mods.

Please, do not fuel a false information on this forum, the reality and the fact do not match your statements, there are some 900whp stock 6 speed trannys (Autoplus) working fine.

Carlos

 

Back to the initial topic, I find the Evo to have a very strong tranny. I had other sports cars with trannys that not even compare in the same league to an Evo.

A good example of disastrous underachiever transmission design in moder age is the Subaru WRXs, they do not hold absolutely any source of abuse.

Even if you haven't ever abuse a WRX transmission you can't even shift to first gear from a roll.

Anyway, that is my opinion

Carlos