why's tried tranny oil in engine to clean up sludge with success?

[look 171]

One my my workmen has a Toyota Tundra with a little clacking that sound like lifters. I know it should be leak in the exhaust because when we rev the motor just a little the sound goes away. When the motor is rev ever so slightly, the sound goes away and it settles down then the noise comes back within 30 seconds. I am thinking of dumping a car of transmission oil in there to try and clear things up. When we were kids, a friend dumped a qt of tranny oil in his motor to try and clean it (read it in some book), drove it around a couple of days and drained his motor after that. He completely ruined his engine. I know to run it just about 5 min after it warms up. Anyone has any luck with that? I like to get this guy back on the road without having to spend money on pulling the heads. Truck has 240,xxx miles

[manbridge 74]

The phosphorus and sulfur in gear oil will waste the bearing shells in short order.

With the mileage just do him a favor and go ahead and do it.

[Tobra]

It is automatic transmission fluid that is used, not gear oil. Has a very high detergent content. I believe you put in a quart of transmission fluid, fill with motor oil and then run motor, with no load on it, for a few minutes to circulate the stuff.

[fastfredracing]

I would stick to more like a few ounces. At one time , Mazda's factory bulletin fix for noisy lifters was a few ounces of dexron right into the engine oil. I remember doing this when I was a young grunt in the biz, and the cars would quiet up in just a few minutes after adding it .
These were all brand new, or cars with very low miles under warranty.

[manbridge 74]

Don’t know why I read that as manual trans oil....

Must be cause I’m stuck with manual trans cars/trucks. I never learned to drive an automatic trans.

You can also try 8-16 ounces of diesel fuel if the dexron (basically 10w oil with more detergents) doesn’t help.

[look 171]

Originally Posted by fastfredracing

I would stick to more like a few ounces. At one time , Mazda's factory bulletin fix for noisy lifters was a few ounces of dexron right into the engine oil. I remember doing this when I was a young grunt in the biz, and the cars would quiet up in just a few minutes after adding it .
These were all brand new, or cars with very low miles under warranty.

drain and refill with oil only after that, right?

[john70t]

If my motor oil is really dirty I'll bump the key and rotate it a couple times to try and get it all out. Not run it.
There's probably a few places where the heavy stuff gets trapped, such as inside the pump.

Voodoo advice here.

[VincentVega]

I think something like mystery oil and atf scratch the same itch. I would change oil after a few hundred miles at most, but that depends on how much crud is in the engine.

[speeder]

Originally Posted by look 171

drain and refill with oil only after that, right?

Originally Posted by VincentVega

I think something like mystery oil and atf scratch the same itch. I would change oil after a few hundred miles at most, but that depends on how much crud is in the engine.

MMO is the same as ATF, just clever marketing. I'd add some ATF to it, (doesn't take much), drive for a couple days and then change oil and filter. Works like a charm.

I've seen people basically rebuild an engine by dumping some ATF in it and driving a few hundred miles on the freeway. We're talking an old truck, burning oil and smoking like crazy, (would have needed to be torn down and rebuilt anyways so no risk), the ATF somehow cleaned or unstuck the rings and compression came back, no smoking, good as new.

[Tobra]

Originally Posted by look 171

drain and refill with oil only after that, right?

yes

[VincentVega]

Originally Posted by speeder

MMO is the same as ATF, just clever marketing. I'd add some ATF to it, (doesn't take much), drive for a couple days and then change oil and filter. Works like a charm.

I've seen people basically rebuild an engine by dumping some ATF in it and driving a few hundred miles on the freeway. We're talking an old truck, burning oil and smoking like crazy, (would have needed to be torn down and rebuilt anyways so no risk), the ATF somehow cleaned or unstuck the rings and compression came back, no smoking, good as new.

Ive seen it a few times, you really dont believe it until you see it. I've also seen soupy, chunky oil drain out after some MMO. Sometimes the oil is just black. Weird.

[faverymi]

Has anyone done it on a 996 or 997 porsche motors?

Those are noisy, including mine.

Just wondering. I can live with ticking noise not without an engine.

[wdfifteen]

Originally Posted by speeder

I've seen people basically rebuild an engine by dumping some ATF in it and driving a few hundred miles on the freeway.

This would be funny if not posted on a automotive message board, where people should know better.
You may get some symptoms to go away by pouring stuff in the oil, but unsticking a lifter is a long way from rebuilding an engine - that is unless you've got some elixir that will straighten out tapered cylinders, reform worn piston rings and bearings, and remove fatigue cracks from connecting rods and crankshafts.

[john70t]

If 'rebuild' was only meant to be a 'theoretical description' (remember Motor Meister and no legal definition on the books)..
And to describe making the parts fit together well again..
That word might work...Or not.

Perhaps 'reconditioning' or 'realigning' an engine would be a better choice.

[Bob Kontak]

I put a quart of anti-sludge stuff in an 84 year old's truck. 84 being meaningless except he used to have an oil change shop and provided the anti sludge in a quart can. It was ancient.

Looked ok going in. Ran for a few. Changed oil. Within one week there was so much sludge in the new oil we changed it again

I don't know if it was the solvent or the motor had massive sludge and this stuff just soaked in or other.

Caveat is just check the new oil's condition for the first week or so.

[wdfifteen]

Originally Posted by john70t

If 'rebuild' was only meant to be a 'theoretical description' (remember Motor Meister and no legal definition on the books)..
And to describe making the parts fit together well again..
That word might work...Or not.

I'll go with "not." I've rebuilt dozens of engines. It's an expensive and painstaking process and there are a lot of gray areas (should I replace that crank, or can I grind it 30 under and still stand behind the job?). Pouring stuff in the oil should be referred to as "de-gunking" or something more descriptive of what is actually being done. The "Rebuild in a Can" myth ought to be laughed at by anyone who knows anything about cars.

[john70t]

(you are correct, I was just being argumentative of course)

[Scott Douglas]

I'd recommend trying some SeaFoam in it.

[look 171]

Originally Posted by Scott Douglas

I'd recommend trying some SeaFoam in it.

Thanks Scott. I completely forgotten about Seafoam. I have never put any of it in the crankcase before. This is the Toyota you sent me a link to a few years ago. We drove out to OC and bought it. Its has a strong running motor, doesn't burn a drop of oil and tranny shifts well. Front end has been done.

[Scott Douglas]

My experience with Sea Foam has only been with cars I don't own, but it seems to have worked OK.
One was an old Chevy pickup w/200k miles on it that I helped a neighbor resurrect for his son. He was given the truck which had been sitting for some time. We put SF in the crankcase and the gas tank. The truck is working fine out in AZ last I heard.
The other time was when my brother and I resurrected a '72 El Camino he'd bought for cheap. We got it running after it had sat for 20+ yrs. Put SF in the crankcase as we'd pulled the valve covers and it was pretty sludged up considering it only had 55k miles on it. Car started up fine with no valve noise what so ever, which really surprised us. Elco turned out pretty nice but he's since sold it. Engine never had any problems while he had it, but 350's are pretty bullet proof.