What causes sludge???
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Short of the obvious of not changing frequently enough... If someone does change their oil every 3000 miles... what other factors would cause sludge build up?
Racer
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From: Kalamazoo MI
Originally Posted by REDC4CORVETTE
Engine running to rich ,engine not comming up to operating temp.
A non detergent oil.
Dirty air cleaner.
PCV not working and sucking oil into the engine,mass quanities.
A non detergent oil.
Dirty air cleaner.
PCV not working and sucking oil into the engine,mass quanities.
improper sealing piston rings
leaking head gasket allowing coolant into crankcase
Team Owner
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From: SE NY
Cruise-In II Veteran
A quality motor oil contains detergents to clean the metal, dispersants to suspend wear particulates, corrosion inhibitors to prevent build up of acids and other chemicals. Over time these addeties can be used up or can deteriorate.
When oil is not changed frequently enough to meet the needs imposed by the service, a phenomenon know as "dump out" can occur. Here suspended particulates and other substances plate out on metal surfaces within the engine.
When oil is not changed frequently enough to meet the needs imposed by the service, a phenomenon know as "dump out" can occur. Here suspended particulates and other substances plate out on metal surfaces within the engine.
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From: Oakland CA
Like a number of my posts this may be tangential. Speaking of sludge, I had a '51 Mercury (sorry).255 inch flathead. It had a bypass filter oil filter. Cracked the crank so I had to go through the engine. There was a layer of gray claylike stuff in the oil pan about 1/4 inch thick. I read some where that the combination of leaded gas and non detergent oil could lead to that. Supposedly a lot of that junk was lead. Other than that the engine was pretty clean.
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From: Oakland CA
And futhermore, do a google for toyota sludge. They apparently have had some serious issues starting in 1997 up 2001. Apparently the pcv was changed and made less efficient and the gasses stuck to the hot engine parts,
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Originally Posted by RatC4
And futhermore, do a google for toyota sludge. They apparently have had some serious issues starting in 1997 up 2001. Apparently the pcv was changed and made less efficient and the gasses stuck to the hot engine parts,
Thanks for the heads up... any other suggestions?
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From: San Pedro CA
My best friend is an a-line tech at a Dodge dealer. We have discussed the Mopar sludge problem more then once... here is the scoop:
1) It does exist... but not the way most people think!
2) Most of the engine failures have been with poorly or non-maintained engines. We are talking 30k miles on the original oil!
3) 3.8 litre V6s seem to be the biggest victims. The sludge builds up and blocks off oil flow to the rockers. Once that happens, the top end seizes... game over. This applies to any engine, really, but he has seen more 3.8s and 3.3s then anything else.
4) How to avoid? Use any good oil, be it conventional or synthetic and change every 3k~5k miles with a good filter.
Oh, one more cause for sludging is heat... conventional oils cannot deal with over heating as well as synthetics.
Over the summer, I helped Ivory90 install an Edelbrock base and runners on his 1990. The valley was loaded with sludge around #1 and #3 cylinders!!!! At the time, I expressed my concern with the engines longevity. I hope it holds up... my worries surround the fear that goo could enter into the pump and or filter... I did an O/C, but told him to do another - FAST - so none of the solids could mess things up.
1) It does exist... but not the way most people think!
2) Most of the engine failures have been with poorly or non-maintained engines. We are talking 30k miles on the original oil!
3) 3.8 litre V6s seem to be the biggest victims. The sludge builds up and blocks off oil flow to the rockers. Once that happens, the top end seizes... game over. This applies to any engine, really, but he has seen more 3.8s and 3.3s then anything else.
4) How to avoid? Use any good oil, be it conventional or synthetic and change every 3k~5k miles with a good filter.
Oh, one more cause for sludging is heat... conventional oils cannot deal with over heating as well as synthetics.
Over the summer, I helped Ivory90 install an Edelbrock base and runners on his 1990. The valley was loaded with sludge around #1 and #3 cylinders!!!! At the time, I expressed my concern with the engines longevity. I hope it holds up... my worries surround the fear that goo could enter into the pump and or filter... I did an O/C, but told him to do another - FAST - so none of the solids could mess things up.
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From: Cincinnati, Oh USA
Sludge is the result of a reaction between water, oil, and suspended dirt particles. Changing the oil and oil filter at the manufacturers recommended interval will dramatically reduce the buildup.
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Bogus - I am not trying to combat you or your friend... but if you do a Google search for Dodge sludge or Durango problems, this was very prevalent in the 5.9's and with people who swear they maintained the motors.
The reason I posed the question here is because I just bought the Dakota RT, and I wanted to make sure there weren't some precautions with the vette and cougar that I should not over look.
I appreciate the info!!! I do regularly change my oil and will continue to do so... I'm also going to check the PCV and other things suggested. I can't say I rememeber one on the LT4... but I don't have it in front of me so I can't say for sure.
The reason I posed the question here is because I just bought the Dakota RT, and I wanted to make sure there weren't some precautions with the vette and cougar that I should not over look.
I appreciate the info!!! I do regularly change my oil and will continue to do so... I'm also going to check the PCV and other things suggested. I can't say I rememeber one on the LT4... but I don't have it in front of me so I can't say for sure.
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From: Dallas/Spring Texas
I have two friends who are techs at Lexus (toyota) and they had done many of the "sludge jobs" in their time there. They too said it was mostly on these old people's cars who didn't change the oil for 15,000 miles or more. The only difference between the old and the young that have the problem is that the young are smart enough not to admit they didn't do proper maintenance. Remember, believe half of what you see and none of what you hear==>(read on the internet).
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Originally Posted by sickspeedvette
I have two friends who are techs at Lexus (toyota) and they had done many of the "sludge jobs" in their time there. They too said it was mostly on these old people's cars who didn't change the oil for 15,000 miles or more. The only difference between the old and the young that have the problem is that the young are smart enough not to admit they didn't do proper maintenance. Remember, believe half of what you see and none of what you hear==>(read on the internet).
with you... and believe me, I'm not taking claims as fact. If I didn't change my oil for 10k miles and my motor blew up under warranty... you damn right I'd be lying and saying I change my oil ever 2k miles!!! Why fess up and take it up the pooper when you can lie and hope to god you get away with it... 
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From: San Pedro CA
Originally Posted by kwik_silver
Bogus - I am not trying to combat you or your friend... but if you do a Google search for Dodge sludge or Durango problems, this was very prevalent in the 5.9's and with people who swear they maintained the motors.
The reason I posed the question here is because I just bought the Dakota RT, and I wanted to make sure there weren't some precautions with the vette and cougar that I should not over look.
I appreciate the info!!! I do regularly change my oil and will continue to do so... I'm also going to check the PCV and other things suggested. I can't say I rememeber one on the LT4... but I don't have it in front of me so I can't say for sure.
The reason I posed the question here is because I just bought the Dakota RT, and I wanted to make sure there weren't some precautions with the vette and cougar that I should not over look.
I appreciate the info!!! I do regularly change my oil and will continue to do so... I'm also going to check the PCV and other things suggested. I can't say I rememeber one on the LT4... but I don't have it in front of me so I can't say for sure.
The key is this: change the oil, it won't be a problem. For every messed up motor he has seen, he has maintained 50 that have zero problems.
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From: St. Peters MO Sometimes you have to prove yourself by doing alot of killing or alot of dying...
Originally Posted by bogus
welp... I donno what to tell ya. He has replaced enough of these motors, and I don't remember him ever mentioning the 5.9 as being one he has done... and we talk a LOT! I will ask him again.
The key is this: change the oil, it won't be a problem. For every messed up motor he has seen, he has maintained 50 that have zero problems.
The key is this: change the oil, it won't be a problem. For every messed up motor he has seen, he has maintained 50 that have zero problems.
I guess I'm more confused on how a company like Dodge or Toyota can experience such a problem during a period of time, yet nothing during any other period... if that make sense. Either way I'm not overly worried, I just want to know what precautions I can take to avoid that.
By the way, you are now needed in St. Louis more than ever!!! I still need to put a system in the vette... my wife blew her rear speakers in her cougar... and I have a monster system to put in the dak
I got beer and your choice of 2 rooms to stay in
I'll see you soon right 
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From: San Pedro CA
Originally Posted by kwik_silver
If you can ask him... I'd appreciate it!!! I do agree that maintanence is key in any motor. It is something I don't plan on overlooking. More often than not I generally change my oil every 2700 miles.
I guess I'm more confused on how a company like Dodge or Toyota can experience such a problem during a period of time, yet nothing during any other period... if that make sense. Either way I'm not overly worried, I just want to know what precautions I can take to avoid that.
By the way, you are now needed in St. Louis more than ever!!! I still need to put a system in the vette... my wife blew her rear speakers in her cougar... and I have a monster system to put in the dak
I got beer and your choice of 2 rooms to stay in I'll see you soon right
I got beer and your choice of 2 rooms to stay in
I'll see you soon right
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Joined: Jan 2002
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From: Edmonton AB
So, are we talking synthetic or mineral oil?
For BMW's from 2000 forward, the factory schedule
for oil/filter changes specifies 15,000 mile intervals.
Those cars are running synthetic. Their schedule for
pre-92 cars is every 7,500 mi and calls for mineral oil
in these cars. For a look, scan halfway down here.
Personally, I would like to see data logs of oil
temperature from vehicles with histories of sludge.
A Jetta we owned from new and recently sold had
changes at about 2,000 mi, far more frequent than
called for. Yet the dipstick was rusty and the area
inside the filler cap opening of the rocker cover was
unpleasant. I will never forget a Buick 430 I opened
up to replace a rocker - I threw away the rocker shafts
because I couldn't get the urethane-like muck out of
them. I also knew the history of that car from new
and it had been maintained.
I suspect both the Jetta and the Buick suffered from
both extremes: oil not warm enough and oil too warm.
.
For BMW's from 2000 forward, the factory schedule
for oil/filter changes specifies 15,000 mile intervals.
Those cars are running synthetic. Their schedule for
pre-92 cars is every 7,500 mi and calls for mineral oil
in these cars. For a look, scan halfway down here.
Personally, I would like to see data logs of oil
temperature from vehicles with histories of sludge.
A Jetta we owned from new and recently sold had
changes at about 2,000 mi, far more frequent than
called for. Yet the dipstick was rusty and the area
inside the filler cap opening of the rocker cover was
unpleasant. I will never forget a Buick 430 I opened
up to replace a rocker - I threw away the rocker shafts
because I couldn't get the urethane-like muck out of
them. I also knew the history of that car from new
and it had been maintained.
I suspect both the Jetta and the Buick suffered from
both extremes: oil not warm enough and oil too warm.
.