[DCx 98GT]

My 01 cobra is making some weird noises form the rear and trans. I hear and feel a clunk when I shift in to almost all the gears, seems like it only happens when I let the clutch out after completing a shift I get the rearend clunk. Also Ill be driving about 30 mph and let off of the gas and give it a slight bump maybe 300 rpm or so and I get a quick clunk coming from the rear. Also why the hell does my trans make so much noise? You can hear all the gears workin and meshing when you shift. Usually from a dead stop if im in neutral and put it in to first I get a clunk, like im puting an automatic in to gear, but from there if i move the shifter from first to second (still at a stop) its smooth. Is the trans a known problem in the cobras? What type of trans is it? Also do you think it is a broken u joint or loose drive shaft? Thanks for the help.

Justin

[DoubleONegative]

Mine 01 does the same thing and so does another guys i know. Welcome to the 01 Cobra club

It's that crappy 3650 tranny

My buddies 03 Cobra does it as well

[CrimsonCobra_01]

I hear ya, when i first got my 01 cobra i was flippin out cause of that noise. Thought i bought a piece of crap. You can feel it too. Im glad im not the only one with the problem, however it cant possibly be good on the tranny.

Hard to believe that the 03 cobras do the same thing

Anyone know if that is fixable or gonna cause the trans to mess up?

[djtech]

Originally Posted by DCx 98GT

My 01 cobra is making some weird noises form the rear and trans. I hear and feel a clunk when I shift in to almost all the gears, seems like it only happens when I let the clutch out after completing a shift I get the rearend clunk. Also Ill be driving about 30 mph and let off of the gas and give it a slight bump maybe 300 rpm or so and I get a quick clunk coming from the rear. Also why the hell does my trans make so much noise? You can hear all the gears workin and meshing when you shift. Usually from a dead stop if im in neutral and put it in to first I get a clunk, like im puting an automatic in to gear, but from there if i move the shifter from first to second (still at a stop) its smooth. Is the trans a known problem in the cobras? What type of trans is it? Also do you think it is a broken u joint or loose drive shaft? Thanks for the help.

Justin

Sounds like the normal Cobra Clunk. There are things you can do to help with these noises but they don't cause any harm. This is how our heavy duty drivetrain works.

If you match your RPM's better when shifting you shouldn't notice it as much when moving.

[DoubleONegative]

mine doesn't do it when i am moving just when i at a redlight and i put into first.

also for the record i hate how pissy the tranny is when it's cold

[Lo Pony]

Most of the noise is the slack in the planetary gears in the traction lok. Some of it is transmission. No, it doesn't hurt anything, but it is annoying as feck.

You might check your driveshaft bolts and make sure they haven't loosened up. I did a nice hard shift one night, had increased clanking and clunking for a couple of days until I decided to investigate. Loose bolts. Couple of blows with a hammer on a wrench around the bolts solved the problem, but you could clearly wiggle the driveshaft rear positioning yoke relative to the flange...this may not be your problem, but it's worth checking.

[DCx 98GT]

yeah i noticed when i concentrate on shifting the clunk smooths out but when im just banging gears around town the clunk is there. I went to a boarders book store the other day (looking for text books for my girlfriend) when I found a mustang tech book in the automotive section. I was reading all the specs on the 01 cobra and it stated that it had a T-45 trans. Iv been reading the on going post in the 4.6 forum about the 3650 trans and how crappy it is. I figure our cars would have a better trans than the gt, so does that mean that the 6 banger trans is the same too? Im not going to mod the hell out of this car I have a 69 camaro that is going to handle all the track duties. I just wanted to know why my car was making weird noises. Ill check the drive shaft and u joints, what whould i expect my dealer to tell me the problem is if I were to take it in? would they just be ok with it or tell me to deal with it. I also was reading in the november issue or 5.0 that there is a ford service posting for loose or broken rear sway bars on 99-03 cobras, I might look in to that too.

[gotven0m]

It's the normal "Cobra Clunk". As far as I know, every Cobra with an IRS has the clunk. There are somethings you can do to quiet it considerably, but I'm not sure it' s possible to get rid of it entirely.

Replacing the bushings in the rear with the Steeda IRS bushings helped a lot in my case. Then after I had the MM bushing installed it made it even less noticable. It's still there, sometimes........But it's DEFINATELY a LOT quiter than it was with the stock bushings.

Also, tightening the nut on my right rear shock helped a lot with the clunk too. It turns out it was loose.

If your tranny is as loud as you are describing, it sounds like you have an aftermarket shifter. They let a LOT of noise come in...

Funny story, I took my car into the dealer to get it looked over before I went on a road trip. He calls back and tells me I need $6,000+ in work because "It sounds like something is broke in the tranny and moving around" and also because "there is a clunk in 5th gear when you left and apply the gas".

[djtech]

Originally Posted by DCx 98GT

yeah i noticed when i concentrate on shifting the clunk smooths out but when im just banging gears around town the clunk is there. I went to a boarders book store the other day (looking for text books for my girlfriend) when I found a mustang tech book in the automotive section. I was reading all the specs on the 01 cobra and it stated that it had a T-45 trans. Iv been reading the on going post in the 4.6 forum about the 3650 trans and how crappy it is. I figure our cars would have a better trans than the gt, so does that mean that the 6 banger trans is the same too? Im not going to mod the hell out of this car I have a 69 camaro that is going to handle all the track duties. I just wanted to know why my car was making weird noises. Ill check the drive shaft and u joints, what whould i expect my dealer to tell me the problem is if I were to take it in? would they just be ok with it or tell me to deal with it. I also was reading in the november issue or 5.0 that there is a ford service posting for loose or broken rear sway bars on 99-03 cobras, I might look in to that too.

I've talked a lot of trash about the T-45. I just hated the way it made my car behave. Others on the board here love the T-45 and honestly mine never failed me. I just didn't feel comfortable driving the way I do on that transmission.

I've gone the route of putting an 03 Cobra T-56 in my car. It has cured all of my complaints and I love it. Now I just need to update my gear to 4.30's and I'll be rockin

If you want to read more on the trans options available go here:

http://www.ttcautomotive.com/English...cts/tremec.asp

The T-56 is rated 350+TRQ and the T-45 is rated 325+TRQ.

In my opinion the T-45 has very weak syncros. That means it won't take long to wear them out if you powershift. I wore mine out in less than 20,000 miles. I don't think the T-56 will wear out nearly as quick.

[gotven0m]

How much in extra parts did it cost for you to change to the t-56? How much was the 03 t-56 and where did you get it from? I've considered upgrading to the t-56 as well, but last I checked there were a lot of hidden costs.....

[djtech]

Originally Posted by gotven0m

How much in extra parts did it cost for you to change to the t-56? How much was the 03 t-56 and where did you get it from? I've considered upgrading to the t-56 as well, but last I checked there were a lot of hidden costs.....

Trans $1550 shipped w/ stock shifter, bellhousing, sensors. Got it from a guy who didn't sell it on EBay and I emailed him offline. Took over 6 months to get that price.

Parts and labor $2000

Billet Aluminum Flywheel, McLeod dual friction clutch w/ King Cobra pressure plate, Firewall Clutch Adjuster, DSS Racing driveshaft, Steeda Tri-Ax, trans mount, bolts misc.

Not cheap but works awesome

[SVTBlackLight01]

Originally Posted by DoubleONegative

Mine 01 does the same thing and so does another guys i know. Welcome to the 01 Cobra club

It's that crappy 3650 tranny

My buddies 03 Cobra does it as well

I just bought an '04 Cobra, and it has this issue as well.

[djtech]

Originally Posted by SVTBlackLight01

I just bought an '04 Cobra, and it has this issue as well.

What kind of flywheel and driveshaft setup does the 04 have? Light weight like the 03?