blew a tranny this weekend
#21
from my previous post, the temps are way too high, but Im sure torque plays a roll well. road racers are not launching and my trans was in gear, for at least a second or 2 out of a corner before it popped so it was not a issue power engagement it was a mechanical failure due to heat, and over time the fluid breakdown and added power caused failure. i'm not an expert but Ive seen several diffs and trans fail in this way on power and I think the heat has a lot to do with it.
red line said it does not really break down till around 400f but they clearly state the viscosity between 200f and 300f is about 1/4, so its like a 3x lighter weight oil at 300 versus 200f.
@ 195 viscosity is 19.5 ( est recommended high temp)
@ 300 viscosity is 6.5 ( this is well into the range you should have a trans cooler)
@ 330 viscosity is 5.5
the 300 temp was based on husler temp sticker, which I presume is a brake temp sticker which simply darkens as each temp benchmark is met. his temp and our temps may be higher
I would really like to see some info on someone who tried a external cooler on a 5 speed and decided it did not work. a setup on a trans that was known to be in good shape.
red line said it does not really break down till around 400f but they clearly state the viscosity between 200f and 300f is about 1/4, so its like a 3x lighter weight oil at 300 versus 200f.
@ 195 viscosity is 19.5 ( est recommended high temp)
@ 300 viscosity is 6.5 ( this is well into the range you should have a trans cooler)
@ 330 viscosity is 5.5
the 300 temp was based on husler temp sticker, which I presume is a brake temp sticker which simply darkens as each temp benchmark is met. his temp and our temps may be higher
I would really like to see some info on someone who tried a external cooler on a 5 speed and decided it did not work. a setup on a trans that was known to be in good shape.
#22
Cpt. Slow
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I was throwing up at your sentence, not your idea.
And like I said please try it. It won't be a waste of money, just time. If it doesn't work it'll bolt up with a little modification to the 6spd you eventually buy. A well placed cooler, an electric pump, a well place return and feed line, and voila. Tell us how it goes and how much it costs. Like I said, I'd love to be proven wrong.
And like I said please try it. It won't be a waste of money, just time. If it doesn't work it'll bolt up with a little modification to the 6spd you eventually buy. A well placed cooler, an electric pump, a well place return and feed line, and voila. Tell us how it goes and how much it costs. Like I said, I'd love to be proven wrong.
#23
In gear for a second or two so its not torque?
How about the increased torque in gear after a second or two as the revs rise and the boost builds?
In the weakest gear in the box, which is allowed the most flex due to being in the middle of an unsupported shaft in a gear where you are getting 100% traction.
Thats got nothing to do with why is failed in 3rd after a second or 2 in the gear?
Dann
How about the increased torque in gear after a second or two as the revs rise and the boost builds?
In the weakest gear in the box, which is allowed the most flex due to being in the middle of an unsupported shaft in a gear where you are getting 100% traction.
Thats got nothing to do with why is failed in 3rd after a second or 2 in the gear?
Dann
#24
Granted, most of the transmissions we build go into cars that are launched more than road-raced, but that does not stop 3rd gear from being the most damaged individual gear we see. Even from a roll or a smooth upshift, the teeth on 3rd will shear off given enough power.
I'm definitely interested in seeing results from this, and your plan for pumping the oil as well. Not trying to discourage you, just tossing in my .02 from seeing lots of trans damage. If you come up with something that can save a bunch of money for a lot of guys, in the long run it'll totally be worth the effort.
I'm definitely interested in seeing results from this, and your plan for pumping the oil as well. Not trying to discourage you, just tossing in my .02 from seeing lots of trans damage. If you come up with something that can save a bunch of money for a lot of guys, in the long run it'll totally be worth the effort.
#25
I'm simply saying that I think heat is causing damage to the gear faces which eventually causes failure. if the torque was the issue, it would rip the teeth off almost as soon as you put on a turbo. I'm pretty sure the gear is getting worn out prematurely due to the due to a lack of sufficient lube caused by excessive heat. one the gear faces get worn the lack of a tight fit causes the gears to smack together and fail. this is a fair hypothesis. I'm sure the torque is a factor but I don't think the torque is killing the trans.
my first step is to send the fluid to get checked out and we shall see what they say. I think I can get a pump for nothing so would just need to figure how to lay out some fittings. my the end of the week I will have the trans pulled and I will take some pics.
has anyone done a cooler ?
my first step is to send the fluid to get checked out and we shall see what they say. I think I can get a pump for nothing so would just need to figure how to lay out some fittings. my the end of the week I will have the trans pulled and I will take some pics.
has anyone done a cooler ?
#26
Granted, most of the transmissions we build go into cars that are launched more than road-raced, but that does not stop 3rd gear from being the most damaged individual gear we see. Even from a roll or a smooth upshift, the teeth on 3rd will shear off given enough power.
I'm definitely interested in seeing results from this, and your plan for pumping the oil as well. Not trying to discourage you, just tossing in my .02 from seeing lots of trans damage. If you come up with something that can save a bunch of money for a lot of guys, in the long run it'll totally be worth the effort.
I'm definitely interested in seeing results from this, and your plan for pumping the oil as well. Not trying to discourage you, just tossing in my .02 from seeing lots of trans damage. If you come up with something that can save a bunch of money for a lot of guys, in the long run it'll totally be worth the effort.
#27
Here's the last few seconds of life in my 5-speed. As you can see, I was in 3rd for the corner, then when I put the throttle down for the straight it went bang. The tire screech is from the red car in front of me
The car has an MSM 6-speed in it now, with a 3.9. I've got a 3.6 R&P sitting on the bench waiting to go on the diff that just came out.
Note that it's $600-1000 for the 6-speed, but you really need to swap the rear end as well. The 4.3 would be useless, the 3.9 is annoying with a turbo, the 3.6 ought to be a lot better.
The other option is the Quaife gearset for the 5-speed, but the gears alone are $2500+ and I've heard (anecdotally) that the increased strength isn't enough and they still break.
--Ian
Last edited by codrus; 05-07-2012 at 11:36 PM.
#28
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2. They break in AUTOCROSS. A cooler will help on track, sure, but not in an autocross situation.
#30
if I need a 3.6 R&P, what car does this come out of and where can I find out. I think I recall reading they are expensive and hard to come by. so what will the effect be if I leave the rear end the way it is? I doubt the 6th gear is shorter then the 5 in the 5 speed. if so that sucks big time.
#31
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if I need a 3.6 R&P, what car does this come out of and where can I find out. I think I recall reading they are expensive and hard to come by. so what will the effect be if I leave the rear end the way it is? I doubt the 6th gear is shorter then the 5 in the 5 speed. if so that sucks big time.
#32
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if I need a 3.6 R&P, what car does this come out of and where can I find out. I think I recall reading they are expensive and hard to come by. so what will the effect be if I leave the rear end the way it is? I doubt the 6th gear is shorter then the 5 in the 5 speed. if so that sucks big time.
#33
Hey Phil, if you tear the trans down post some pics of the remaining teeth on your broken gear, or of the other gears which survived, or both. Some good overall shots, and some macro shots that show both sides of the teeth, so that the surfaces are clearly viewable. That will go quite a ways towards figuring out what happened.
#35
I wonder if I can get it from mazda speed discount program for racers, anyone checked this out?
Yeah was going to do it today but I had to work. I will have it out by the end of the week for sure. I was going to go pick up a six speed this week but now I'm not sure I want to deal with taking apart the diff just to achieve the same gear ratio. if anything I would like a slightly taller gear. its possible the po may have done a shorter final drive for drifting.
I'll get some pics for sure, speak up if they are not good enough. perhaps I'll have you build be me one good for 1000 whp!
Yeah was going to do it today but I had to work. I will have it out by the end of the week for sure. I was going to go pick up a six speed this week but now I'm not sure I want to deal with taking apart the diff just to achieve the same gear ratio. if anything I would like a slightly taller gear. its possible the po may have done a shorter final drive for drifting.
I'll get some pics for sure, speak up if they are not good enough. perhaps I'll have you build be me one good for 1000 whp!
#36
I wonder if I can get it from mazda speed discount program for racers, anyone checked this out?
Yeah was going to do it today but I had to work. I will have it out by the end of the week for sure. I was going to go pick up a six speed this week but now I'm not sure I want to deal with taking apart the diff just to achieve the same gear ratio. if anything I would like a slightly taller gear. its possible the po may have done a shorter final drive for drifting.
Yeah was going to do it today but I had to work. I will have it out by the end of the week for sure. I was going to go pick up a six speed this week but now I'm not sure I want to deal with taking apart the diff just to achieve the same gear ratio. if anything I would like a slightly taller gear. its possible the po may have done a shorter final drive for drifting.
The 3.3 is the gearset that many people want with the 6-speed, but it's unobtanium and may even be mythical.
--Ian
#37
The 3.3 is the gear set that many people want with the 6-speed, but it's unobtanium and may even be mythical.
so what should my 99 be in the rear? according to this article my final drive should be 3.3 but the axle ratio is 3.9, what number should I be looking at. my car has a 5 speed but I believe it was replaced with a 95 trans due to a failure. so it sounds like the 6 speed is stock for a 99? I'm still new and learning the year to year changes so bare with me.
http://www.motortrend.com/roadtests/...a/viewall.html
so what should my 99 be in the rear? according to this article my final drive should be 3.3 but the axle ratio is 3.9, what number should I be looking at. my car has a 5 speed but I believe it was replaced with a 95 trans due to a failure. so it sounds like the 6 speed is stock for a 99? I'm still new and learning the year to year changes so bare with me.
http://www.motortrend.com/roadtests/...a/viewall.html
#38
so what should my 99 be in the rear? according to this article my final drive should be 3.3 but the axle ratio is 3.9, what number should I be looking at. my car has a 5 speed but I believe it was replaced with a 95 trans due to a failure. so it sounds like the 6 speed is stock for a 99? I'm still new and learning the year to year changes so bare with me.
http://www.motortrend.com/roadtests/...a/viewall.html
http://www.motortrend.com/roadtests/...a/viewall.html
Your 99 is a 4.3 unless it's a 10th anniversary edition (10AE), in which case it's a 3.9. The MT article is about the 10AE. The 10AE is the only 99 that came with a 6-speed.
NA 1.6s came with 4.3.
NA 1.8s came with 4.1.
NBs with 5-speeds came with 4.3
NBs with 6-speeds came with 3.9 or 4.1 (varies by year)
This is all in the USA and for manual transmissions. Other countries and automatics may be different.
http://solomiata.com/RingandPinion.html
--Ian
#39
I'm going to go pick up a 6 speed because I still have a lot to do on the car and I dont have time to dick around. I strongly considering mounting a spare temp probe in the drain plug just too see what the temps are inside. I have a some vdo gauges from an old project I can use.
should I open the case to inspect the gears before I install?
the leak I was experiencing was coming from the trans, not the engine so I think i'm going to leave the rear main alone for now and just put the new trans in. or should I really order rear main and trans seals?
what do you guys think about adding a heavy oil to the trans. like 75-110 or 75-110? most people run 75-90 right?
should I open the case to inspect the gears before I install?
the leak I was experiencing was coming from the trans, not the engine so I think i'm going to leave the rear main alone for now and just put the new trans in. or should I really order rear main and trans seals?
what do you guys think about adding a heavy oil to the trans. like 75-110 or 75-110? most people run 75-90 right?
Last edited by psreynol; 05-11-2012 at 11:30 AM.
#40
https://www.miataturbo.net/album.php...pictureid=2406
what do we need to post a picture, Ive tried the baisics but i'm doing it wrong
what do we need to post a picture, Ive tried the baisics but i'm doing it wrong