This Horrible transmission noise :S

[iceberg65]

Just hoping to get some input on this noise; if anybody s experienced something similar. (linked because photobucket videos don't seem to in-bed properly)

http://s237.photobucket.com/user/iceberg65/media/20160902_192601_zpsubpv3v1w.mp4.html?sort=3&o=0

Symptoms; this horrible noise is more noticeable from the drivers side; it occurs only in gear including reverse. It goes away once the car is moving faster then about a brisk walking pace. It sounds almost like the parking pawl is not fully disengaging.

The speedo cable has come out of the transmission; and the gear is still in there (could be wedged in somewhere causing issues). The car has the small stall little green converter in it (not sure on specs). The linkage from the floor shift is solid but the one up to the column is fairly sloppy. The engine makes very little vacuum at idle but trans seems to shift fine while driving.

I think my best bet is to pull the pan and the valve body and see what I can see with the trans still in the car; then if that doesn't get me anywhere; pull it and most likely rebuild. But thought one of you may have something for me to try.

 

[Bentworker]

FMX C4 or C6?

I'm with you on the parking pawl.

I bet that it will be apparent once you pull the pan

 

[iceberg65]

forgot that key info haha; its a c6

 

[iceberg65]

Well as I thought about it I realized that I would see the parking pawl better with the tailshaft housing removed rather then dropping the pan.... so I did that today..... and found nothing wrong...... it's engaging and disengaging just fine; no broken springs or random objects to be found. The parking pawl is not whats making the noise.

Any chance that something bad in the converter could be causing this sound? again it only happens in gear while not moving or at very low speed.

The converter in it is a little green converter that my dad got from a swap meet years ago; it didn't look like anything was wrong with it; but you cant really see much of a converter externally.

 

[72HCODE]

Could be the pump behind the converter.

Possible broken sprang deep in the trans.

Leaking dry rotted internal seals causing low pressure and things not fully engaging at low speeds

You would have to take apart everything to inspect for the point or points of failure.

I wouldn't want to waste money on a new torque converter as a possible solution until the rest of the trans was inspected and cleaned out.

 

[iceberg65]

Yea thats kinda the conclusion I've come to myself as well, the car did sit for 9 years. I have another converter but it's a big stock converter and the small stall would be really beneficial to retain on the 4v Cleveland. I'f I'm pulling the trans; it's worth rebuilding and doing some upgrades. C6 parts are pretty cheap, and I dont have to pay a shop to do it so it makes sense.

 

[iceberg65]

Well I got the trans out and haven't looked closely yet; but the kickdown lever pulled right out of the linkage which cant quite be right.

Aaaand; I think I have a busted stator support collar (I'm not familiar with trans internals this is just from what i've seen of em torn apart in videos) but the outer splined collar was like wanting to come out with the converter. I'll be looking at it closer on saturday.

 

[72HCODE]

yeah the kick down has a nut on the back holding it together to the gear select so there is or was a nut bouncing around in your trans, best case its sitting in the pan.

the inner splined shaft in the center of the pump comes out, the outer spline is part of the pump housing, if that wants to come out then you have major mechanical damage as it is part of the statutor support.

the stat suppport is bolted to the back of the pump the pump housing is bolted to the C6 case.

before you start just ripping it apart, you need to drop the pan and take some measurements of the play between the back of the stat support and the high clutch drum face.

you need to see how out of spec it is or isn't so you have a reference for reassembly otherwise you need thicker or thinner shims.



if you want to see some of the internals before taking it apart here is my teardown of my bad trans which i replaced with another c6 and rebuilt that as well.

http://s1031.photobucket.com/user/72hcode/library/thesmokinggun?sort=2&page=1

my old C6 was in VERY poor condition so it made sense to swap for another one in much better starting condition then upgrade it a little.

my car is originally an FMX so swapping trans didn't matter.

i went through 4 transmissions to build one good one.



left my original c6 which was complete junk all bushings worn out and it was from a 1974 station wagon.

middle 1972 Q code C6 trans which would of been perfect except it was in an accident and the main case and tail housing was Cracked. i stripped it for parts and a better lever and servo

right late 1980s truck transmission different cooler line fittings. and case changes used for parts Swaped the foward and rev(high) drums from it as they were 4 band units the originals were 3 band.

also had anti clunk design.

all went into a 1973 mustang transmission that was my last choice but it was in excellent internal condition just needed some new bushings and seals and swap in parts. used raybestos clutches and a red alto wide 2nd gear band. got a NOS original steel sprang for it as well. so basically i mildly upgraded it and then installed a TCI Saturday night special torque convertor.

i opted not to install a shift kit or modify the valve body.

 

[iceberg65]

Oh wow; great info Hcode! that album is awesome thanks! I'll definitely make note to check that clearance. I think it was most likely the inner collar that was coming out with the converter; it was getting dark and i didn't pull it right out; it was just lose as I was dragging it out from under the car. The car did still shift and drive ok; it just had the very prominent sound in gear at stop and low speed.

I'm taking it to a mechanic friend of mine to go over it with me; hes built a good number of autos and is a fan of c6 and TH400 builds. I've got a good amount of mechanical knowledge but the innards of an auto are one thing I haven't touched, so I'm looking forward to learning from him. His fee; I learn and maybe help him out on his sonoma (that runs around 800hp when turned up).

I'm already thinking Its a good idea to see what I can get for donor transmissions for parts too; luckily that shouldn't be a problem as my dad is a ford part packrat and uses the manual stuff on his car and just never uses the auto's he has sitting around.

I'm holding off on deciding what I'm going to until it's apart; however this is going to see strip time so a performance rebuild is likely; and I'm looking into shift kits and valve bodies; but thats also something that can be done later too if need be.

 

[72HCODE]

i never rebuilt a trans before; Until last year.

my C6 nuked itself in about april 2015

i decided screw it here is my shot at rebuilding one.

i knew i had the wrong c6 for a mustang so a couple of members gave me some junk mustang C6s because they converted to 4 speeds or they just had them laying around. I drove out of state just to get some of them, free is free

check out my threads

http://www.7173mustangs.com/thread-the-curse-of-the-blown-transmissions-strikes-again

http://www.7173mustangs.com/thread-help-me-find-a-torque-convertor

http://www.7173mustangs.com/thread-the-confusing-world-of-transmission-fluid

http://www.7173mustangs.com/thread-lets-talk-about-c6-servos-and-levers

----

take a read through all those there is some good info in there.

you can rebuild it yourself you will need some tools and i would recommend getting the C6 video from bad shoe productions.

http://www.badshoeproductions.com/

the video really helps you to understand the shop manual and gives you a how to visual guide you can follow along with.

I went a little crazy since i took it upon myself to not only rebuild something i had never been inside before but also modify it heavily in some ways and mildly in others.

there are also some free c6 rebuild videos online that have some more tips that are good

i read up and watched some videos bought the tools and so far a year later my rebuilt trans is still working.

i also rebuilt my 3rd member a couple of years ago.

when i completed my trans rebuild and installed it in my car; based on my knowledge i then cracked into my old broken transmission to confirm what i thought happened and why it failed. i found additional terrible work performed by a transmission place that worked on it.

basically i took the time to build up a better trans as a noob then some crappy trans shop had done.

it took me about a month or 2 to get all the parts and tools i didn't have to work on a c6 but once i had all the stuff it all went together in a couple of hours.

now i could if needed rebuild another C6 in about a day if i had the master kit and new clutchs and steels.



it really isn't that bad you break down all the assemblies into chunks, then put the chunks together it is pretty straight forward.

don't skimp if something looks questionable just replace it.

 

[iceberg65]

Yea thanks again; I have some good reading material in your threads there. I've already gone over a couple videos; tons of info on these c6's and really not an overly complex assembly. Tools are no issue for me; I have a pretty good amount of tools myself; and for any specialty stuff my twin brother has been a professional mechanic for 12 years; I can borrow anything I need. I'm really quite lucky on that front.

Doing my build with my other friend is my plan as he's done a lot of these for all kinds of applications (including some pretty strong drag cars) and is also a journeyman mechanic. I'm sure by the time I'm done researching and learning I'll also have a great understanding of it.

I hear ya on trans shops not always doing a great job; I had one install a diff for my cougar a while back; and I know they didn't do the job as well as it should have been done for the cost. They used the wrong sealer; and didn't locktite a carrier bearing in (the bolts backed off within a couple weeks. Luckily I caught it and the bolts were accessible from the outside of the case. Never again; I'm better off being hands on.

 

[iceberg65]

The major problem was immediately obvious upon tear-down, I confirmed that my stator splines had in fact broken off.



I'm thinking this failure was caused by the last engine the car had (or moreso it's removal) The motor had locked up so it got pulled out with the converter still attached. My guess is that in all the jostling and bumping to get it all out from the car; it stressed the shaft and cracked it along the way; then as soon as it got loaded up it let go completely.

The kick-down lever did not leave a nut in the pan; it left the internal lever for it there. Looks like it was just braised in place and that had let go.



The whole trans was due for a rebuild anyway; the band was worn; and the first gear clutches were all worn out and left heat marks on the steels; the 2nd gear clutch pack also had one of them installed incorrectly in it; the inside collar was bent up and binding on the drum splines.

I will say I am amazed that the car drove like it did now that I've gotten into this gearbox.

I'm touching base with a c6 guru for his input first but am currently looking at a full 500hp rebuild kit from broader performance.

 

[72HCODE]

pretty surprising it kept going the stat being cracked must not of been spinning otherwise the pump would of stop supplying fluid pressure around the trans it was loosing pressure through the cracked stat but it was back leaking internally into the trans.

watch out with replacement pumps there are some C6 differences through the years. so do not throw out your old pump (stat) before you double check it against the replacement.

if you wish to restore the linkage you will need a donor trans from a mustang or cougar. nobody sells it separately, i don't have extras unfortunately i was really lucky to get one original linkage off a busted 72 trans, the 73 mustang trans i got was missing all the linkage because it was sold to somebody else before it was donated to me. Don at OMS might have what you need he can strip out from an old c6.

the rest of the stuff is obtainable from various transmission places.

 

[iceberg65]

Good to know; there are at least 4 c6's that I have to pick off of only one was a small block bellhousing though all are older castings. I'll see if one has the lever I need; otherwise I may be able to repair whats there somehow it looks like it was just braised from the factory.

The shaft wasnt just cracked; it was completely broken off. It came out with the converter loose.

 

[Bentworker]

Wow! That is some carnage

 

[iceberg65]

That it is;

I've now ordered my full overhaul kit; I found that i have a newer style case in my car so it's been swapped out at some point. I also grabbed an extra c6 for scavenging whatever else I may need.

After talking to a guy near me thats been building c6's for years behind 1000+hp engines and even builds his own (very popular) transbrake valvebodies for them I concluded that I'd just add an extra clutch in the high/reverse drum, and put in a transgo reprograming kit into the valve body and it'll hold whatever I throw at it for my application.

 

[iceberg65]

I got my transmission back together; I added a clutch in the direct drum as well as in the forward drum. Clearances on the drums are .47 in the direct drum and .35 in the forward drum. Reverse clutches are around .48 but tricky to get the feelers in there good.

My endplay is a bit loose though at .55; gonna have to get a thicker selective washer for it to get below .44

Other then that I also put a transgo reprogramming kit in the valve body. Not too much more work until I can put er back together.

 

[iceberg65]

Got the trans back in, endplay is nice and tight now at .010. Drove the car and ran it through the gears and all is working as it should. Just need to get the carb and timing dialed in still. Gonna run a new vacuum line to the modulator too.

Sent from my SM-G920W8 using Tapatalk

 

[Jeff73Mach1]

Well done!