Hi Everyone, I have a 2001 Cadillac Eldorado with about 19,000 original miles. It has the Northstar engine which is known to gum up the piston rings with carbon resulting in oil usage. Also the engine is known to leak alot of oil. I want to try the Valvoline to clean the rings and other parts but afraid it might also attack the engine seals. The caddy is a little noisy when cold and doesn't leak any oil. I only drive it about 500 miles per year so don't think it uses any oil. The car was dealership maintained on bulk oil until I received it, changed once per year regardless of mileage. Anyone care to comment? Thanks
2001 Cadillac Northstar and Valvoline Restore and Protect
- Thread starter Lance G
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Don't think it'll hurt the seals so I'd use it. Change every year regardless of low mileage if it makes you feel well. Your car your money. More importantly try to put high octane ethanol free gas in it. Some stations sell it while others don't.
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This is common issue with the N* I have had 2 of them and they both did it. They get a lot carbon on the piston tops, the answer is not to do a full plugs out piston soak but running a can of GM top engine cleaner through a vacuum line slowly, shutting it off and let it soak for a few hours takes care of it. Today it is still available but pricey.
You can try running a a few bottles (one bottle per tank) through the fuel system, after about 500 miles of use give it a high rpm highway run and don't be surprised if you see a black cloud behind you.
if the oil is API and ilsac licensed, it won't attack the seals any worse than any other approved oil, it's tested for that. That is unlike over the counter additives that have no regulations to adhere too, and seal compatibility is a legitimate concern.
I'd say that would be a perfect oil for a Northstar. Oil VII's wern't really up to the task of the high piston heat when those were being produced, so yeah, coked up ring packs.
Annual oil changes would be my suggestion, but you could actaully go two years without an issue.
Don't forget the WOT, those Northstars thrived on that! I think it was second gear that was to be used.
Annual oil changes would be my suggestion, but you could actaully go two years without an issue.
Don't forget the WOT, those Northstars thrived on that! I think it was second gear that was to be used.
Yep! (with it warmed up to temp) shift the stick to 2 and put the pedal through the floor. the Northstars absolutely love it. 
the trick is after you hold the revs up as long as you dare to let off the gas hard and let it cruise down under high vacuum. apparently this engine braking type of load is the primary benefit to this technique. I think I understand enough to see how this could make sense. in terms of it creating higher cylinder temps and greater exhaust pressures to really blow the crud out.
the trick is after you hold the revs up as long as you dare to let off the gas hard and let it cruise down under high vacuum. apparently this engine braking type of load is the primary benefit to this technique. I think I understand enough to see how this could make sense. in terms of it creating higher cylinder temps and greater exhaust pressures to really blow the crud out.
There is lot of RTV in the N* engines like some other engines that use RTV for sealing, ester oils are not good with RTV it turns it into slimy string and results in leaks.
Some of the modern RTV are not as affected but were not used when these engines were built. Most grp III synthetics are fine, many stop leak and other additives are not.
Some of the modern RTV are not as affected but were not used when these engines were built. Most grp III synthetics are fine, many stop leak and other additives are not.
You really don't need to hit the rev limiter. 5000 or so rpm will do just fine.Yep! (with it warmed up to temp) shift the stick to 2 and put the pedal through the floor. the Northstars absolutely love it.
the trick is after you hold the revs up as long as you dare to let off the gas hard and let it cruise down under high vacuum. apparently this engine braking type of load is the primary benefit to this technique. I think I understand enough to see how this could make sense. in terms of it creating higher cylinder temps and greater exhaust pressures to really blow the crud out.
Thanks for all the replies thus far. I ordered the Restore and Protect and will be using it in the Caddy along with a new filter. Since it's only driven 600 or so miles per year, might leave the Restore oil in it 2 years and change the filter after 1 year, don't know yet. Engine does appear very clean when looking into the oil fill. My main concern and reason for the VRP is the gumming up of the rings that can occur on this engine.
I usually take the car out about every 10 days and run it about 20 miles to warm everything up. I usually stomp on it pretty hard after it's warmed up to keep the carbon out! Concerning the fuel, I have been using 93 octane with ethanol but only pumping in about 5 gallons at a time to keep it fresh. Might switch to Sheetz 90 no ethanol. Have used some Seafoam when I first got it but might put some dedicated fuel cleaner in.
Thanks again.
I usually take the car out about every 10 days and run it about 20 miles to warm everything up. I usually stomp on it pretty hard after it's warmed up to keep the carbon out! Concerning the fuel, I have been using 93 octane with ethanol but only pumping in about 5 gallons at a time to keep it fresh. Might switch to Sheetz 90 no ethanol. Have used some Seafoam when I first got it but might put some dedicated fuel cleaner in.
Thanks again.
Agreed. I've never seen Seafoam do anything much different than WD40. You want to be using a good "fuel system cleaner", not a fuel additive / stabilizer or "fuel injector clearer". Anything like Techron that gives a good dose of PEA (Polyetheramines).
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I wonder where Hondabond RTV stands with oils made with mostly ester or oils with significant percentages of ester.
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The transverse Northstar holds like 8qts of oil doesn't it? It's been a long time.
My old mechanic friend told me that Cadillacs w the northstar are good as long as you drive it. He daily drove his and had no real issues
7.5 quarts with filter. Supposedly the engine was designed to run up to 50 miles without any coolant in it if something failed. Probably the reason for the large oil pan capacity.
I’m sorry, we’re not going to comment on the museum piece that is a 2001 N* with 19k on it??
WOW, very cool. What a survivor.
WOW, very cool. What a survivor.
