Gm cracked flex plate knock

The noticeable symptoms are a rattling or crackling noise at idle, similar to the sound made by the heat riser in the older engines. The classic and most obvious symptom of a cracked flexplate involves the sound it makes while the engine is running. Is there a recall for defective flywheels flex plate. A loose bolt on a flexplate or a crack between its bolt holes. Bad knock on engine people say flex plate on 1979 gmc 350.

The part apparently is not expensive, but the labor is a killer. A rattling noise the behind engine loose flywheel bolts. Thought they saw a crack in flex plate, i have a warranty that covers the flex plate, i had to authorize the removal of trans for further inspection, but the shop said the spacer looks bad and they found no cracks. Dec 27, 2016 spark knock constant when under load or fast rev in neutral. It is possible that the flex plate is loose,or cracked. Flywheel, automatic transmission flexplate, plate description. Looking for the gm part number for the flex plate torque converter dust cover. Under load massive fuel knock duramax first generation. Descriptions of the sound include clanking, chirping and a light knocking. Nov 16, 2006 it has a few thousand miles since the trans rebuild. It didnt fix the noise but now when i start the truck it sounds pretty bad only while. Jun 19, 2007 cracked flexplate sounds very close to a rod knock. When a flexplate cracks, it often produces a loud knocking noise as it rotates.

This may occur in worn engines or engine that have been poorly rebuilt. Broken or loose bolts on the crankshaft end of the flexplate, or on the torque. Loose flexplateconverter bolts make a nasty sound similar to a rod knock, but immediately go away as soon as you try to accelerate the mass. If a thud is heard, the flywheel may be loose or damaged.

Loose flexplate converter bolts make a nasty sound similar to a rod knock, but immediately go away as soon as you try to accelerate the mass. If its near where the trans and engine meet theres a possibility its the flex plate. I dont think i used enough locktight when installing it. I had the transmission rebuilt thinking it was the flywheel or torque convertor and wasnt the problem but transmission was in bad shape.

Jan 06, 2015 im swapping a 4l80 into my 1997 k1500 suburban w5. Is there a recall for defective flywheels flexplate. Those factors ensure that when the engine starts and the driver puts it in. I did check the converter bolts and they were good. Any metal shop can make you one using the cracked one as a pattern. It could be anything from a timing chain to a cracked flex plate sounds like a timing chain slap to me. Broken pistonpin, loose rod or main bearing, who knows. I would take that cover off and turn the flywheel by hand to see if you can see a loose bolt. Worn pilot andor cracked flex plate issues return on the gm 4l80e converters. Flywheels and flexplates chevrolet performance offers.

I have the same kind of knocking noise but i know what the problem is. I think the shifts are setup too hard on the computer causing the flex plates to break actually. I have seen a bunch where motor was pulled for said rod knock and broken flex plate was found. Broken or loose bolts on the crankshaft end of the flexplate, or on the torque converter side, missalign the flexplate, causing a high side of the plate to strike or rub against internal components. I had the usaf metal shop make me one from a scrap of aircraft grade stainless. If you have a knocking noise from your engine it might not be the engine itself. Ok, so i replaced my flexplate 290,000 miles to see if that eliminated the lower end noise in my engine. To me it sounded like a mad woodpecker somewhere under the truck. It is critical that you use the correct design for your specific engine application. Chevrolet performance 10185034 chevrolet performance flexplates compare flexplate, 168tooth, external engine balance, 1piece rear main seal, chevy, big, block, 454 7.

I have seen on occasion the torque converter bolts get loose and. But i doubt that, so we will say you have an automatic transmission and this means you have a flex plate, not a fly wheel. If its a two piece seal 85 or older 350, just get a 153 tooth flexplate for a 250 six or a 307 v8, itll work fine on the 350. Gm performance view topic broke my fourth flexplate. I believe it is a cracked flexplate because i have a vibration when converter locks. It has a pinging noise from the engine when accelerating from a stop. Flywheels and flexplates chevrolet performance offers both internally and externally balanced flywheels and flexplates. With the car running listen for where the knock is coming from. Noise in my chevrolet silverado sounds like flywheel.

Cracked gm flexplates are pretty common, and make a heck of a rattling noise. Since that time i have had to replace the flywheel 3 times and it needs it again. And he says he has to pull back the transmission, etc. Mar 21, 2010 i was told by several people it could be a cracked flex plate. I have been told by a repair garage that i have a broken flex plate on my 88 yj, at, l6.

Random rattling noise from bellhousing area the truck stop. I just thought id post a short video of what a cracked flexplate on a 6. Discussion in chevygmc 4x4 started by 74 chev, feb 27, 2010. Im not ruling out possibly a cracked flex plate but im leaning away from it. I have not grounded out any plug wires to test for rod knock yet. My chevy started this tick noise out of now where thought about it and yea its the flex plate.

No codes but seems to have a miss, have adjusted valves, have a even 175180psi in all cylinders. Loose flywheel or flexplate bolts make a rattling or knocking sound that. As i was driving into work this morning i noticed a sound that seemed to come from the middle of the car. A cracked flexplate is almost always a sign of other problems. Oil pressure is good, 45 at idle up to 75 at 4500 rpm. The tci superquality flexplates are thicker than stock plates to withstand the stresses of todays high rpm engines and highstall torque converters. The truck still runs great and doesnt effect performance at all. It seems the centrifugal force kept the plate from popping as it turned at higher speeds. Most of the cracked flexplates ive heard sound worst at idle. It is common either to build up the pilot by welding and then.

A loose or cracked flywheel will produce an irregular thud or click. This truck gonna get a lq4 and 4l60e eventually save to say i love her. I was told by several people it could be a cracked flex plate. My uncle thinks it may be a cracked flex plate from how i described it to him.

Is there a recall for defective flywheels flexplate 2004. An old fellow stopped by my shop last year in an old nice eldorado cadillac convertible. These do occasionally crack and will need replacing. Loose torque converter bolts and cracked flex plates. My 1990 gmc sierra has less than 20k on my complete new drivetrain engine. Has new fuel pump, upgraded spider injector assy, cap,rotor,coil, egr gasket, intake gaskets. I cammed the engine and used solid mounts originally which caused excessive vibrations etc. Last time i hunted the exhaust, lifters, bearings, only to find out i had to do the damn flex plate and it only had 2030k on it maximum.

It has a few thousand miles since the trans rebuild. Slight misalignment may only cause a single flexplate to break in the life of the vehicle. At first i thought it was comin from the top but when i get under it its alot louder sounds like its comin from the oil pan. He had just come from the dealer and they told him the knock in his engine was the main bearings and quoted him an ungodly price to repair. A loose bolt on a flexplate or a crack between the bolt holes can result in the same knocking or. It bolts to the end of the crankshaft and the transmissions torque converter bolts to it. And no, i cannot see anything with the inspection cover off. In this video i talk about a noise coming between the engine and transmission. The flex plate replaces the flywheel in automatic transmission cars. Oil filter was clean no silver in the filter that was noticeable on the element and very very little residue on the filter mag. Your flexplate could also be cracked as well, certainly not unheard of on a 6.

This saturday i slid the torque converter off the flex plate and got the engine hot. If its a rod knock, you can make the sound change or go away by pulling off each plug wire one at a time. But when you raised the rpm to a middle level the knock went completely away. The reason for the sound involves the flexplate s location and its function. What can i do to troubleshoot this aside from dropping the trans and inspecting. If the flex plate is cracked, there will be one solid knock sound when you turn the key back on. I have a loud knocking noise coming from the engine. The reason for the sound involves the flexplates location and its function. Does this have an auto trans, maybe a cracked flexplate. Chevy 168tooth plates have dual bolt patterns to accommodate both powerglide and turbohydramatic th torque converters. If it really is the flex plate, thats a lot cheaper than other problems that could cause a bad knock. Most torque converter rebuilders routinely deal with the undersize pilots on gm 298mm converters.

No noise what so everi took the trans out and the flex plate looked like brand new with no cracks. This video demonstrates the sound, diagnosis and solution to what sounded like a rod knocking on a 1999 toyota 4runner with a 3. How to know if a flexplate is warped it still runs. Similarly, a cracked flywheel will offer some great noises like a rod, ect. Usual failure mode is the crankcase bolts or the torque converter bolts work loose, allowing the parts to start moving in different directions, the clicking sound you heard. The problem turned out to be a cracked flex plate which. Ive read the threads, but cant find the part number im looking for.

When mine was cracked, it even made the car idle rough. I was told that a small crack in the flexplate could mimic the sound of rod knock or piston slap. New crate motor knock discussion in the hokey ass message board started by timewr, jul 5. May 27, 20 you can isolate a broken flex plate by bringing the rpms up to about 1800 and keep it steady. Excessive crankshaft flange runout or end plate can also cause flexplate cracking. Your crate motor may have come with the flex plate on it. It runs fine in park but in any other gear with my foot on the brake it has a very noticeable, almost loud knocking sound. Noises are really hard to pin down, especially long distance through the net. I hadnt removed the inspection plate yet to see if i had a broken tq converter bolt or a cracked flex plate. Has anybody had any luck welding up cracks in a 6 cyl flex plate. In the past few days my 94 has been knocking while in gear and at low rpms. I had a cracked flexplate on my 74 that was a hard knock sound like a rod bearing at idle and low rpm.

Im not trying to start a panic here, only encouraging you to get some way to look at livedata so we can minimize guessing. I had posted a similar question when i first got my vehicle around sep. Jeep grand cherokee questions is it common for a loose flex plate. The flex plate is a steel plate that bolts to the rear of the engine and has gear teeth. Jan 27, 2009 the engine was installed in 2000 and 6 months late i blew up the transmission thats when i had a sfi rated flex plate installed.

Way more information than you ever wanted on how to fell a tree. It may be as easy as removing a small torque converter cover or it may. When you hit the right cylinder with the bad rod bearing the sound will quit or get much. Cracked fly wheel usually gets louder as it gets hotter, or under heavier load. If its anywhere else id be making him pay for the new engine. I have the back seats out so there isnt too much sound dampening back there, and i have been listening for any odd noises over the past few weeks. Chevrolet silverado 1500 questions loud knocking noise 5. I had am issue with my chevy silverado and after your video i sent and took it a. Proposed the issue was the flex plate rather then the engine. I just thought id post a short video of what a cracked flexplate on a. To test for a loose or cracked flywheel, operate the vehicle at approximately 32 kmh 20 mph and shut off the engine. Jul 05, 2012 is the flex plate made for the one piece rear main seal crank. One bolt loosened up just a hair and cracked the plate. A warped flexplate can make metaltometal contact with the inspection plate cover, or the starter drive mechanism, and can also make a knocking.