tranny noise? update coming from flexplate area

[91waggy]

I have a ticking maybe tapping noise that I think might be coming from the tranny? The noise does not occur in park or drive. It occurs under normal acceleration after being driven around a mile or two. The noise stops when the tranny shifts but continues after its done shifting. If the wag is slowly brought up to speed then it won’t make the noise. Sometimes it won’t make the noise at all under norm or hard accel. The engine was replaced less than 1000 miles ago. When the engine was installed it was first done so with the bushing for the manual tranny installed in the crank, the engine was tightened to the housing(it was removed and the truck was never started with it like that). Any suggestions I love the truck but I have spent a lot on this thing and it keeps wanting more attention. :mad: 1991 amc 360 229 transfercase and tf727 tranny

[ January 20, 2004, 04:53 PM: Message edited by: 91waggy ]

[andy d]

the pilot bushing may have broken or damaged the pump housing on the 727. this is posted from time to time.

[Mo'Gas]

I had a similar noise I think, sort of sounded like a bent pushrod or bad lifter tick, ended up that the flexplate had a small crack in it.
I spent the extra dough to get a SFI approved one when I replaced it.

[91waggy]

btt

[Ralph]

I would check the flexplate first. I've seen these cracked around the holes for the bolts to the torque converter.

The inspection is fairly easy. There is a plate on the bottom driver side that can be removed with just a couple of bolts. This is the smaller plate shown in this picture:
http://i8.ebayimg.com/02/i/01/06/32/d4_1.JPG

You will be able to see the flex plate mated to the torque converter. By bumping the starter, you can turn the flexplate over enough to see each of the four bolt holes this way.

[91waggy]

Thanks I will look again. I checked to see if the crank was moving a couple weeks ago because of the same noise, however it was quieter then. It sounds like its coming from that area. It is loud now and even does it idling in drive. If it’s the crank bearings again and the cranks moving I don’t know what I am going to do. It just got a brand new motor and fuel injection. Just eats every part hmmm... seems to fit :rolleyes:

[Ralph]

My experience with a cracked flexplate was in Dutch's old Grand Wag, when I took it on a long road trip from Ohio to Florida in January 2002, pulling a 2400-lbs. trailer in order to pick up a set of doors in Atlanta (from billyrb) and a complete frame/body from Madison, FL.

The noise seemed most prominent when decelerating. I kept thinking it was an exhaust manifold leak. But when I got back to Ohio, a mechanic advised me to check for loose torque converter bolts. Sure enough, the flexplate had cracks radiating about an inch on either side of all four bolts holding it to the torque converter. It looked as if it would eventually create a circular crack all the way around the flexplate.

It's a simple matter to check on this; however, it's a bit more work to replace the flexplate since the tranny has to be moved out of the way.

[Rick78J10]

May I ask what fuel injection you are using? Cam, intake, exhaust?