R154 chatter 1200-1500RPM

[7Mboost]

My transmission is chattering at 1200-1500 RPM then it goes away and doesn't come back only that 300RPM range. It sounds like something loose, I'm going to pull the inspection plate tomorrow to see if I can visually see any problems but what else should I look for and has anyone experienced a similar problem? I am certain the clutch and flywheel are torqued to spec.

 

[shenronzero]

7M: i hope its not anything serious. i really dont know if this would have anything to do with it or possible but could you somehow be low on fluid?

is it in certain gear(s) or is it in all gears?

 

[7Mboost]

All gears.

 

[shenronzero]

damn... i hope everything goes well.

 

[tissimo]

My old trans made a chatter noise at idle (only time I heard it), it lasted 1 year with ~ 450whp then it started popping out of 1st.

 

[bassjunkiens5]

Tear it down asap!

 

[7Mboost]

Tear it down asap!

That'll get you post count up! Have any reasoning behind that suggestion?

 

[bassjunkiens5]

I could care less about post count. Input shaft bearing is going bad and causing the gears to bind.

It's causing a harmonic effect like a v-twin bike but only in your trans meaning something is loose and/or going bad. Typically what's stated above.

 

[7Mboost]

I could care less about post count. Input shaft bearing is going bad and causing the gears to bind.

It's causing a harmonic effect like a v-twin bike but only in your trans meaning something is loose and/or going bad. Typically what's stated above.

Pulling the tranny tomorrow, my dad is saying he doesn't think its the input shaft bearing because it will still do the noise in 4th gear, he's saying it shouldn't make noise in 4th gear because of its position or something, anyone know what I'm talking about?

 

[Zumtizzle]

what kind of gear oil do you use?

Xx-90wt?

but hmm. nothing to be alarmed about unless you plan on beating on the car.

 

[black89t]

I could care less about post count. Input shaft bearing is going bad and causing the gears to bind.

It's causing a harmonic effect like a v-twin bike but only in your trans meaning something is loose and/or going bad. Typically what's stated above.

thats a bold statement. where the hell do you get that idea? what is going to cause that? that bearing has the least amount of stress. it supports the smallest shaft in the tranny next to rev idler shaft. thats about the most unlikely bearing to fail in the whole tranny. :rofl:

its actually the OUTPUT shaft bearing on the intermediate plate. thats what mine did and sounded like you described yours. your 1st gear thrust washer has been tearing that thing to shit and the bearing is most likely seized. better take it appart before its too late.

 

[black89t]

Pulling the tranny tomorrow, my dad is saying he doesn't think its the input shaft bearing because it will still do the noise in 4th gear, he's saying it shouldn't make noise in 4th gear because of its position or something, anyone know what I'm talking about?

if a noise in a tranny goes away in 4th thats usually something to do with the counter shaft. becasue the power is going straight from the input shaft to the output shaft putting no load on the countershaft so the noise goes away.

it might be your diff though. does it wine? you want to be positive you know its your tranny. pull the shift boots off and drive around. you should be able to tell where the noise is coming from. if it is coming from the tranny i can almost gaurantee thats your problem.

 

[7Mboost]

if a noise in a tranny goes away in 4th thats usually something to do with the counter shaft. becasue the power is going straight from the input shaft to the output shaft putting no load on the countershaft so the noise goes away.

it might be your diff though. does it wine? you want to be positive you know its your tranny. pull the shift boots off and drive around. you should be able to tell where the noise is coming from. if it is coming from the tranny i can almost gaurantee thats your problem.

Its definitely coming from the tranny, I'm gonna finish pulling it out tomorrow.

 

[black89t]

are you planning on rebuilding it yourself? getting parts from champion will save you $$$. just make sure you talk to jeff.

 

[Doward]

Jeff, yank it out and check everything. I've got no problem helping you rebuild the tranny if you want - as a matter of fact, that'd get me motivated to finish my own r154 build

 

[grimreaper]

is this chatter like luggin the motor since its WAYYY out of the power band? think starting off in second at 900 rpms,

 

[adampecush]

Input shaft bearing is going bad and causing the gears to bind.

This was my first thought as well...I had the exact same problem on my first supra - would get a nasty chatter/low rumble when taking off under 1500 rpm.

 

[black89t]

^what caused it to fail? the bearing on there seems pretty stout. its also sealed, so it can't dry out. i'm curious what would cause it to fail. and in 4th there are no gears to bind. so with that theory it should go away in 4th.


when the output shaft bearing fails there become massive play with 1st gear so it wobbles around making racket in practically every gear eventually popping out of 1st because the sleeve slips of the gear because the gear walks toward the intermediate plate.

 

[Poodles]

The bearing is stout, but the bearing cover plate is not.

That's why marlin makes a better plate...

 

[black89t]

^if your talking about the input shaft bearing there is no mc replacement. the mc bearing retainer is for the mainshaft bearing and countershaft bearing on the intermediate plate....