r-154 rejecting shifter when put in 3rd...

[Insidious Surmiser]

what's up w/ this... my transmission w/ 107k miles on it, doesn't really like being shifted into 3rd... the fluid level is where it should be, and it didn't used to do this... i'm using the correct viscosity of valvoline syn. the problem only happens occasionally, but it really hates shifting into 3rd @ high rpms :-/.... just curious what's up w/ it, because it seems thins is a common occurence in r-154's

 

[MDCmotorsports]

Both shift bushings are worn.

There is a clear polly busying on the tip, and a green bushing on the ball of the shifter.

 

[Insidious Surmiser]

is that all? i mean it acts like the syncro's are out too :-/

edit: likes to grind in all sorts of situations, same for 2nd and 4th... 3rd is the worst though

 

[supra90turbo]

I'd say full rebuild time...

 

[Insidious Surmiser]

yeh, i was gonna say that too , just wanted to check first

 

[Nick M]

edit: likes to grind in all sorts of situations, same for 2nd and 4th... 3rd is the worst though

Those are symptoms of worn synchronizer rings. The grinding is the pointed clutching teeth out of sync. The pointed teeth are there just to hold it in gear, the groves on the inside of the ring are the problem.

A teardown will tell you the full the truth though.

 

[IJ.]

Syn can cause this as well being too slippery to let the Syncro's do their job correctly....

 

[Insidious Surmiser]

too slippery?

 

[IJ.]

Yep too slippery

the syncro works through friction so it can match speeds between gears speeding up the gear one way and slowing it down the other.

If the Oil is too slippery this doesn't happen and you get a clash on the change (My Tremec's doing this ATM)

 

[Insidious Surmiser]

so could syn. tranny fluid be doing this? like i stated in the first post (the type of oil)

 

[IJ.]

It's possible!

 

[Insidious Surmiser]

i guess i'll try non synthetic lube then, see if that'll help... that oil cost me a lot (just think back when your 2 week pay check = 100$)

 

[IJ.]

Get a really clean tray to drain it into then a clean container to store it just in case!

The Syncro rings and their mating surfaces can glaze up a bit so it might not come good right away.

There are additive packs esp for baulky syncros I tried one and it actually made things worse.

 

[Insidious Surmiser]

aight, i'll do just that, and i don't like additives :-/