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Once you hit OD, highway cruise is under 2k rpm. How much would you get in trade vs what a scrapper would pay for it as it sets? Around here, the numbers aren't far enough apart to justify it. Even in my current state, i bet i get under $1k in trade, vs a $250 quick dump to a scrapper.

it goes over 2500rpm at around 45, and would kick into OD at 48-50. soon as it his OD though there is absolutely zero power, and it loses speed then drops out of OD and thrashes all to hell. where i have to go is a 55mph speed limit, and tons of cops who would frown on any car that tootles along at 30-35 sounding like this. i also have no idea how long it will even run in this state. i reiterate 30 miles. i am afraid to leave my home with it. if it self-destructs, there is zero shoulder to pull over to, and i have no $ to pay impound fees. i do not even have cash to pay the fee to tow it off.

the one last drive to the park and back was 7 miles each way. i got the nerve-wracking sweaty palmed grip on the wheel as it sounded worse and worse after each mile. third gear shift made it quiet but it doesn't like speeds over 30. sits overnight and start it sounds more normal but put into gear and drive one mile it does it again. when this started it was sudden, and at the time my oil gauge was showing 40psi, going to around 70 on take-off. now it is completely dead which i am unsure whether or not the sending unit is shot or not. i still get oil to the valve covers as i noticed with it running without them on. clean oil too. still zero sign of metal.

When it hits overdrive at that speed, does the whole car shudder violently?

yup. very badly. but mounts are fine. i checked fluid and it was normal, too. the shaking is my engine pulsating like it is badly misfiring. at higher rpm it sounds like it is badly out of time and runs horridly. is fine below 2krpm.

it makes it to 40mph no problem but refuses to sustain speeds at 40 or beyond for long. you can drive it all day at 30-35 though, so long as you turn the music up loud so you don't hear the woodpecker under the hood.

While I don't like to diagnose issues over the internet, I'm inclined to say you've got a misfire issue badly. Check you wires and plugs. If those check out, go to the coils and check them. I've had that happen to me and both the plugs and wires were very worn, original in fact.

a misfire that only happens in OD?

two things i want to do.

1. drop oil pan and inspect rod bearings (if only for peace of mind)

2. check/replace timing chain and gears (and the camshaft magnet which fell off long before i got the car)

i have tried the old 'pull a plug wire to see if knocking goes away' but noise is still there. just idles rough when i do that.

it is a random, thrashing metal sound, like a few BBs got in the oil and are making perhaps the worst scary sound you ever heard. it ain't rhythmic or in time, just variable intensity.

plug wires got done last fall. plugs a few months before that. hell i had to move it a few feet to mow the grass, and it sounded more normal but it got worse when i moved it back.

I've had a harmonic balancer fail. I'm no expert, but it sure sounds like you have two separate problems. I think the harmonic balancer might have failed. I don't know what the other sound might be, but it does sound like something internal in the engine. It shouldn't be hard to check the harmonic balancer. Pull the serpentine belt off and check the crank pulley. That's a lot easier than dropping the oil pan. As far as 10w-30 motor oil vs straight 30 motor oil, I've got 305,000+ miles on mine with 10w-30 and I've never had a problem with it. 10w-30 is what is recommended by Pontiac/GM. - BC

i have already done that. if the balancer had failed i would be able to rotate it freely a bit each way. it would also go away under load. though a horrific noise on its own, harmonic balancer knock happens most at idle.

it is possible the 30 weight was actually keeping my dying engine alive or masking another problem, one which showed up only after having changed to 'correct' oil. i have heard of some putting 90w gear oil to silence a rod knock. i live by 'if it ain't broke, don't fix it' and if the car had 30w when i got it, 30w is what it gets. 30w is also cheaper. has worked fine in countless used cars.

what i might get from junking it is irrelevant, as 1) i cannot have a useless car sitting in my driveway forever, 2) i have zero means to swap engines here, 3) i need another car, plus i am buying a truck for work, so see #1, 4) people look at you like an idiot if you even attempt to sell them a car with a bum motor.

but before i junk it, i want to know what went wrong and see what it takes.

nickdalzell1 wrote:i have already done that. if the balancer had failed i would be able to rotate it freely a bit each way. it would also go away under load. though a horrific noise on its own, harmonic balancer knock happens most at idle.

When mine failed, it sounded like the car was trying to play a bad set of "chimes", even when driving.

nickdalzell1 wrote:it is possible the 30 weight was actually keeping my dying engine alive or masking another problem, one which showed up only after having changed to 'correct' oil. i have heard of some putting 90w gear oil to silence a rod knock. i live by 'if it ain't broke, don't fix it' and if the car had 30w when i got it, 30w is what it gets. 30w is also cheaper. has worked fine in countless used cars.

it wouldn't be the first time that was done. A long time ago the trick was to add sawdust to the engine oil.

Wish there was some way I could do more to help in the way of knowledge. I am curious as to the cause of all the sounds the car is making myself. - BC

three possibilities i see

1. rod bearings are shot/oil pump sludged up

2. timing chain gears are failing (would explain the erratic running at higher rpm)

3. balance shaft? is that the same as a camshaft?

i doubt it is the balancer as there is no free play. i had a Buick with the LN3 which seemed notorious for it, and it is quite a different noise plus mostly went away during acceleration. my 92 does what sounds like the engine thrashing to bits on acceleration. if i felt like living dangerously (and had money for a tow) i would see what'd happen by flooring it. would know soon enough then.

iirc, i thought sawdust was for noisy/slipping transmissions? something a sketchy used car dealer would do to a clunker to make it ok for a test drive, lasting long enough for the car to get off the lot.

there is a YouTube video of a 3800 engine blow, or rather an impressive failed attempt at one. they took a severely wrecked Buick, removed the coolant, oil, dropped the pan, shot dirt into the intake, fired it up and made it hit the rev limiter. after 6 minutes of horrid thrashing it finally seized the rings. oddly enough in a few minutes it turned over, fired and almost idled.

nickdalzell1 wrote:three possibilities i see

1. rod bearings are shot/oil pump sludged up

2. timing chain gears are failing (would explain the erratic running at higher rpm)

3. balance shaft? is that the same as a camshaft?

I would guess the first out of those three. To me it sounds like something lower, based on the tone of the ring.

The balance shaft is a third shaft in the engine block.

just to ask, is dropping the pan as simple as draining the oil and removing the bolts, or is there something attached that might ruin a good weekend?

nickdalzell1 wrote:just to ask, is dropping the pan as simple as draining the oil and removing the bolts, or is there something attached that might ruin a good weekend?

IIRC, remove the dustcover on the starter, then it's just the bolts on the oil pan. If you're limber, you can do it in 15 minutes or so. - BC

Yep, just did the pan on my LeSabre. Just remove the dust cover like Bill said, then all the pan bolts. If all the rods check out good and you reassemble, use some rtv in the 4 corners of the pan. Once you have it off its easy to see where it would need extra help sealing.

I would recommend cleaning the bolt holes and bolts with spray brake cleaner and putting star lock washers on your pan bolts. IIRC the torque on the bolts is only 8 or 10 ft pounds. If you don't, the bolts might come loose in a little while. If you're adventuresome, you could a little (and I mean a little) green locktite on the bolts and let it dry before you install the bolts. - BC