Transmission Knocking noise only in 3rd Gear?

[Thomas8497]

My car is an 84 T-Bird 5.0 with a 5 speed conversion. I have put about 5 or 6 thousand miles on the t5 I put in place of the AOD. (t5 has about 75k supposedly) recently my transmission has been making a light knocking noise when the shifter is in third gear. It does not do it at any other time. I'm not noticing any loss of power in the other gears. Could this be a shifter issue, or am I looking at a rebuild here?

[homer302]

Usually that type of noise is associated with the throwout bearing but only one gear doesn't sound like the case. I had a plastic speedometer gear come apart in mine one time (and yes, the speedo still worked) and you would be surprised how much noise it made while it was "chewing up" all the plastic inside. I heard it in 5th gear mostly. At least that is easy enough to remove and just look at the teeth on it and it's free. Good Luck.

[ashley roachclip]

is the sound speed consistent , as it gets faster with speed ?
Maybe a chipped gear .

[Thomas8497]

I'm currently running with no speedo gear, just have the speed sensor and cable plugged. But the sound does get faster with speed. I may take it out here soon and take a video.

[Thomas8497]

I'm currently running with no speedo gear, just have the speed sensor and cable plugged. But the sound does get faster with speed. I may take it out here soon and take a video.

[Thomas8497]

[ashley roachclip]

I can hear the same sound when you are in second and fourth.
Tho louder in third , it sounds like an exhaust leak in the video.

[homer302]

Yeah, THAT'S not speedo gear, LOL. You weren't lying. I don't have a guess but I hear whining as well, especially in second. Does this thing have fluid in it? What kind of fluid is in it?

[Thomas8497]

That exhaust leak you're hearing is open headers lol, but I just changed the fluid, I used ATF like the manual says to.

[cb84capri]

Is this a world class or non world class t5? When did this start? Does the car feel jumpy in that gear or is it just noise?

Cale

[Thomas8497]

Non-world class t5 (Supposedly with carbon synchros) and the car feels normal in 3rd, haven't given it any power in 3rd due to the obvious, but it doesn't feel any different except for noise. Started when I was driving around on the weekend in town. Just putting around nothing crazy.

[erratic50]

Time to tear it down and see what's up.

Of course most of the time guys that rebuild T5s only really care about the case so it could be a couple free shots.

[dynodon64]

That's a broken tooth on the third gear. Third gear is the weakest and first one to blow out. Time for a new third and most likely counter cluster shaft.

[homer302]

Third gear is the weakest and first one to blow out.

I will agree with this statement whole-heartedly. In fact, I have a WC T5 missing 3rd gear in my basement as we speak. 2nd trip down the 1/4 at Rockingham Dragway and kablewey! LoL.

[Thomas8497]

I've been calling around places near me and cant find any shops who do rebuilds. How involved of a job is replacing 3rd gear? Taking the trans out is no problem, I just have no experience rebuilding.

[homer302]

What area of the country do you live?

[mmb617]

T5's are pretty easy to rebuild. If you decide to do it yourself I highly recommend Bob Hanlon's video that walks you through the entire rebuild step by step:

http://cart.hanlonmotorsports.com/t5-rebuild-dvd

[cb84capri]

If that is a nwc as you say, third gear may have torn into the main shaft as they are not rollerized like the wc boxes. The non-world class boxes are not worth putting money into. Your best bet is to find a wc t5 and put it in the car. You may be able to use one out of a v6 sn95 car, which seem to be plentiful in junkyards rnow. Haystack on here seems to have had some luck with it, though I haven't done it for myself.

Cale

[ashley roachclip]

I built mine in the front room , on white carpet .
Wife about killed me , but no carpet was harmed .
Only special tools needed are good snap ring pliers , and the wife's oven and freezer .

[Thomas8497]

Well it sounds to me like doing the rebuild myself would be worth it, as well as the experience. Any advice on which kits are better than others?

[cb84capri]

You will be spending good money on a bad transmission if that is a non world class in your car. You can trust me on this, I have had both of them apart next to each other.

Cale

[Walking-Tall]

Why not take the transmission out, check for any/all potential sources for the noise, and/or then pop the top and look for broken parts (gears, etc.) prior to getting parts or lining up or doing a rebuild?

[erratic50]

I would contact Anthony Delross of Marshall MO. He's been building them for years and puts out a quality build.

Grab his contact info - I'll delete it after you have it.
(660) 229-0725
spraystang@yahoo.com

Last I knew Anthony was paying $100+ for broken T5's regardless of condition or miles and pays the shipping. I sold him three of my dead T5s and had him build a T5Z in my original 86 case.

Speaking of selling off stuff of no use to me, I have yet I another recently trashed T5 that I should sell. It's a wonder I haven't just straight up scattered one on the ground yet. Lord knows it's not for lack of trying. Lol.

[Thomas8497]

Unfortunately this car is/was my daily driver and I work full time 20+ minutes away so looks like im saving up for a WC

[Thomas8497]

Update: Dynodon64 called it. Third gear went kaput. Installed a new used world class t5 and.... 3rd gear grinds.