I've had this problem with the T5 in my Cobra clone ever since I've had it, but I've been paying attention to it recently. There's a rattle/vibration in the tranny in low-speed/high torque scenarios. For example, while driving up a parking structure, I'm driving slow in 2nd gear. Taking the turns, I usually coast; when I hit the gas after the turn, I get a rattle for a couple of seconds. If I give it just a bit of gas around that turn, no rattle. I also hear it when shifting from neutral to 1st.
I was under the car this weekend, and decided to check it out, My first thought was the rear end, but I was wrong. With the tranny in 1st, I can rotate the driveshaft by hand about 1/2"; at each end of the rotation, I hear an audible "clack" in the middle of the T5 somewhere. I did not notice any side-to-side movement of the driveshaft yoke nor any play in the differential or the aluminum driveshaft. No other trouble shifting into gear that I have noticed. Some whine in 3rd gear, but that is improving since I put in Royal Purple Synchromax this weekend (which is why I was under the Cobra)
So, the rattle is caused by play in the tranny somewhere, which means a rebuild. Any other ideas? The clutch and t/o bearing are likely OEM Ford; the donor Cobra only had 52K on the clock. Oh, in case it's relevant - I have noticed a slight vibration starting just over 2K RPM's, and it goes up and down with RPM's. It's only a light vibration, easy to miss if the road's a bit rough. The balancer was replaced when I did the driveline swap, a Pioneer 50oz SFI balancer. I'm not sure if the vibration is new or if it's been there the whole time.
I was under the car this weekend, and decided to check it out, My first thought was the rear end, but I was wrong. With the tranny in 1st, I can rotate the driveshaft by hand about 1/2"; at each end of the rotation, I hear an audible "clack" in the middle of the T5 somewhere. I did not notice any side-to-side movement of the driveshaft yoke nor any play in the differential or the aluminum driveshaft. No other trouble shifting into gear that I have noticed. Some whine in 3rd gear, but that is improving since I put in Royal Purple Synchromax this weekend (which is why I was under the Cobra)
So, the rattle is caused by play in the tranny somewhere, which means a rebuild. Any other ideas? The clutch and t/o bearing are likely OEM Ford; the donor Cobra only had 52K on the clock. Oh, in case it's relevant - I have noticed a slight vibration starting just over 2K RPM's, and it goes up and down with RPM's. It's only a light vibration, easy to miss if the road's a bit rough. The balancer was replaced when I did the driveline swap, a Pioneer 50oz SFI balancer. I'm not sure if the vibration is new or if it's been there the whole time.
