Looking for ideas on LS1 replacement
Thread Starter
Advanced
Joined: Nov 2009
Posts: 54
Likes: 0
From: Aurora IL
Looking for ideas on LS1 replacement
Hello,
So my car has been leaking and burning oil a bit so I took it to a Chevy dealer to get a better opinion and they're not exactly sure without pulling the whole thing apart but most likely one of the gaskets. Engine has 150k miles on it so it's not exactly new. My thought and their recommendation was to look at rebuilt LS1. I've never missed a scheduled maintenance on the car and the rest of the car is in pretty good condition so I don't really want to throw in the towel and get rid of just yet!
Are there any good places / recommendations people have for sourcing and having someone install a rebuild or low mileage LS1? Reading through some posts it appears I could also drop a LS6 engine in if it was a good price. If I went down this route what additional items would I have to change if I was going to replace the LS1 with a LS6?
If anyone knows of, or has good references for shops that have carried this out that would be much appreciated. Especially if they can both source and install the engine.
If there's any additional information I can provide please let me know.
Thanks.
So my car has been leaking and burning oil a bit so I took it to a Chevy dealer to get a better opinion and they're not exactly sure without pulling the whole thing apart but most likely one of the gaskets. Engine has 150k miles on it so it's not exactly new. My thought and their recommendation was to look at rebuilt LS1. I've never missed a scheduled maintenance on the car and the rest of the car is in pretty good condition so I don't really want to throw in the towel and get rid of just yet!
Are there any good places / recommendations people have for sourcing and having someone install a rebuild or low mileage LS1? Reading through some posts it appears I could also drop a LS6 engine in if it was a good price. If I went down this route what additional items would I have to change if I was going to replace the LS1 with a LS6?
If anyone knows of, or has good references for shops that have carried this out that would be much appreciated. Especially if they can both source and install the engine.
If there's any additional information I can provide please let me know.
Thanks.
Last edited by _Spare_Ribs_; Dec 23, 2015 at 03:17 PM. Reason: typo
Burning Brakes
Joined: Feb 2003
Posts: 1,144
Likes: 18
From: Panhandle FL
I would find the problem first. Does it smoke out the tailpipe ? If it's not leaking from the valve covers then it's most likely the front or rear main seal. 150k miles isn't a ton for a well maintained LS1. I just did heads and cam on my car with 100k miles. You could still see the cross hatching in the cylinders from the factory. I would say with my new heads, cam , oil pump, timing chain , I have another 100k miles to go.
Now if your just hungry for a new motor, that's another story.
Now if your just hungry for a new motor, that's another story.
Thread Starter
Advanced
Joined: Nov 2009
Posts: 54
Likes: 0
From: Aurora IL
I would find the problem first. Does it smoke out the tailpipe ? If it's not leaking from the valve covers then it's most likely the front or rear main seal. 150k miles isn't a ton for a well maintained LS1. I just did heads and cam on my car with 100k miles. You could still see the cross hatching in the cylinders from the factory. I would say with my new heads, cam , oil pump, timing chain , I have another 100k miles to go.
Now if your just hungry for a new motor, that's another story.
Now if your just hungry for a new motor, that's another story.
It's not smoking out of the exhaust and it doesn't seem to be the valve covers. The mechanic said he thought it might be the rear seal, in describing it to me he mentioned it was at the back and was shaped like a house. I probably should have asked for the more technical term.
I agree with finding the root cause but to he certain it seems like they're going to have to start taking the engine apart or the parts around it, like the transmission to get to it, all the time the $ are ticking so there's also that to consider in how far do I want to go in diagnostics.
I'm not hungry for a new motor and would certainly prefer a "wallet friendly" solution... although don't we all!
I think I will get a 2nd opinion after the holidays.
Burning Brakes
Joined: Feb 2003
Posts: 1,144
Likes: 18
From: Panhandle FL
I would get a couple of cans of brake kleen. Spray around the back of the intake and any other areas that are coated with oil . Get a small mirror and look at the back of the intake. There is a oil pressure sensor back there that sometimes goes bad and can leak. If that's the case, Merry Christmas ! Cheap fix. Either way if you clean the motor it should be easier to track down the leaks .
Race Director
Joined: Mar 2004
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From: Fort Wayne IN
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First off, don't take it to a dealership for a maintenance item like checking into oil leaks. That's just asking for a situation like yours where "we want to pull the motor to look" is the "best" option to them.
Get it to a more routing shop. They'll clean the motor off, and tell you to come back in a couple of days and see if they can pinpoint the leaking. As Speed750 said, you can DIY it also if you're mechanically inclined and want to go through with it.
Once you trace the leak, you can attack the primary cause. Rear main seal would probably be the worst case scenario because the driveline has to be dropped, but therer's plenty of other areas where oil could leak from.
Get it to a more routing shop. They'll clean the motor off, and tell you to come back in a couple of days and see if they can pinpoint the leaking. As Speed750 said, you can DIY it also if you're mechanically inclined and want to go through with it.
Once you trace the leak, you can attack the primary cause. Rear main seal would probably be the worst case scenario because the driveline has to be dropped, but therer's plenty of other areas where oil could leak from.
Pro
Joined: May 2014
Posts: 670
Likes: 46
From: Indiana
I sure wouldn't replace the engine at 150K miles over a leaking rear main seal, or based on their description of something shaped like a house, the gasket for the rear cover. Obviously if one or the other of those two is in need of replacing the other should be replaced as well since it really isn't any more labor.
Keep in mind that dealers don't want to do "speculative" fixes because there's a chance there is more that needs to be repaired and they don't want customers coming back for the same problem after having already charged them a good deal of money for a fix because they are likely to get some bad word-of-mouth advertising from many customers who have to come back. So they recommend a sure-bang fix, even if it costs 10x as much. As far as they know it will motivate some customers to do a trade-in instead of the repair and so it becomes even more motivation for them to recommend the sure but quite expensive fix.
Keep in mind that dealers don't want to do "speculative" fixes because there's a chance there is more that needs to be repaired and they don't want customers coming back for the same problem after having already charged them a good deal of money for a fix because they are likely to get some bad word-of-mouth advertising from many customers who have to come back. So they recommend a sure-bang fix, even if it costs 10x as much. As far as they know it will motivate some customers to do a trade-in instead of the repair and so it becomes even more motivation for them to recommend the sure but quite expensive fix.
Safety Car
Joined: Dec 2009
Posts: 4,363
Likes: 430
From: Birmingham Al
I create LS-3 is the way to go easy install and not that bad of a price ,a friend just had one installed in a 98 he has around $6500 after the install with 480 HP and a three year warranty .. Runs great find one that was built by GM the same as they put in the new Camaro's.. Just an FYI ..
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Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
SO,,,,, YOU WENT TO THE STEALERSHIP... .... 
Please have them ship me your JUNK old engine. I will gladly pay shipping.
On a more serious note.... Your leak is most likely something way less tham a major fix.
If your not a hands on guy and dont want to or cant sluth this out,, PLEASE find a compentent C5 / C6 capable Corvette speciality shop who will be less likely to take advantage of you.
Im sure someone on here from your area can point you in the correct directions for a good honest corvette shop ..
Bill
Please have them ship me your JUNK old engine. I will gladly pay shipping.
On a more serious note.... Your leak is most likely something way less tham a major fix.
If your not a hands on guy and dont want to or cant sluth this out,, PLEASE find a compentent C5 / C6 capable Corvette speciality shop who will be less likely to take advantage of you.
Im sure someone on here from your area can point you in the correct directions for a good honest corvette shop ..
Bill
Last edited by Bill Curlee; Dec 27, 2015 at 08:09 PM.
Le Mans Master
Joined: Jan 2009
Posts: 6,226
Likes: 33
From: Morton illinois
St. Jude Donor '14-'15
First off, don't take it to a dealership for a maintenance item like checking into oil leaks. That's just asking for a situation like yours where "we want to pull the motor to look" is the "best" option to them.
Get it to a more routing shop. They'll clean the motor off, and tell you to come back in a couple of days and see if they can pinpoint the leaking. As Speed750 said, you can DIY it also if you're mechanically inclined and want to go through with it.
Once you trace the leak, you can attack the primary cause. Rear main seal would probably be the worst case scenario because the driveline has to be dropped, but therer's plenty of other areas where oil could leak from.
Get it to a more routing shop. They'll clean the motor off, and tell you to come back in a couple of days and see if they can pinpoint the leaking. As Speed750 said, you can DIY it also if you're mechanically inclined and want to go through with it.
Once you trace the leak, you can attack the primary cause. Rear main seal would probably be the worst case scenario because the driveline has to be dropped, but therer's plenty of other areas where oil could leak from.
exactly. stay away from all dealerships. it should be illegal with the crap they pull. I see you are in aurora, there is a good shop called straighline performance in Joliet. check them out and thy will help with whatever you want done and they will be honest.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The good advice has arrived. Go see what they say and make sure that you reference the Forum.. Please let us know what the outcome is.
Bill
Race Director
Joined: Jun 2001
Posts: 10,084
Likes: 3,056
From: CA
Changing an engine for an oil leak? Have we really turned into that much of a throw away society? Considering people are getting 300,000, 400,000 and even 500,000 miles on well maintained LS1 and LS6 engines, I'd fix the leak.
Michael
Michael
Instructor
Joined: Apr 2015
Posts: 179
Likes: 16
From: Springville Indiana
Dealership diagnosis
A short experience with dealership diagnosis. My 4.3 was hard starting, after new plugs, fuel filter, fuel pressure regulator I decided to stop and have the local GM dealer hook it up to their "state of the art" diagnosis system. They called and explained the heads were shot and needed a total top end rebuild - when I asked the cost it would be $1800, and this was back quite a few years ago. Luckily I didn't let them do the work as my brother said it sounded like something he had seen on another vehicle of his and suggested to try the coil, sure enough 17 dollars later it fired just fine and ran great. I tried to get the dealer to recoup my $75 mis-diagnosis and they adamantly denied the mistake. The service manager said the equipment was latest and greatest and would not have made the mis-diagnosis, the general manager just dismissed it as a fluke. GM said it was up to the dealer discretion to make it right. My credit card company actually ended up refunding my money as a bad purchase ( I'm still with them 25 years later). The van ran fine for another 120,000 miles, before trading it in. Caveat Emptor (let the buyer beware). Good Luck whichever way you choose to proceed.
Le Mans Master
Joined: Jan 2009
Posts: 6,226
Likes: 33
From: Morton illinois
St. Jude Donor '14-'15
A short experience with dealership diagnosis. My 4.3 was hard starting, after new plugs, fuel filter, fuel pressure regulator I decided to stop and have the local GM dealer hook it up to their "state of the art" diagnosis system. They called and explained the heads were shot and needed a total top end rebuild - when I asked the cost it would be $1800, and this was back quite a few years ago. Luckily I didn't let them do the work as my brother said it sounded like something he had seen on another vehicle of his and suggested to try the coil, sure enough 17 dollars later it fired just fine and ran great. I tried to get the dealer to recoup my $75 mis-diagnosis and they adamantly denied the mistake. The service manager said the equipment was latest and greatest and would not have made the mis-diagnosis, the general manager just dismissed it as a fluke. GM said it was up to the dealer discretion to make it right. My credit card company actually ended up refunding my money as a bad purchase ( I'm still with them 25 years later). The van ran fine for another 120,000 miles, before trading it in. Caveat Emptor (let the buyer beware). Good Luck whichever way you choose to proceed.
that should be illegal, and they should be fined. that is complete bs
Thread Starter
Advanced
Joined: Nov 2009
Posts: 54
Likes: 0
From: Aurora IL
ok so I took it to D&M Corvette and got them to do a diagnostic.
As suspected by the dealership, it's the rear seal and additionally the cover gasket. Along with that they said it will need the transmission service done to change the oil and filter there too. I guess that makes sense if they have to separate the transmission from the engine.
Total is about $1900. I guess that's less than getting an engine rebuilt or looking for a used one but not exactly a cheap fix either.
I see the good ole dealership has taken a beating in this thread, as usual, but in their defense they didn't pressure me into buying anything or using their service and they showed me the car up on the lift so I could at least see things for myself. Their suggestion of looking into a rebuild may not be that far off the total cost, given more items could be uncovered when I have the rear seal / cover gasket replaced which could bump the price up more. I understand they have their ups and downs and are not for everyone but I don't think you can tarnish them all with the same brush. That said, a second opinion is always a good idea and sometimes it's worth paying a bit more for a specialist.
As suspected by the dealership, it's the rear seal and additionally the cover gasket. Along with that they said it will need the transmission service done to change the oil and filter there too. I guess that makes sense if they have to separate the transmission from the engine.
Total is about $1900. I guess that's less than getting an engine rebuilt or looking for a used one but not exactly a cheap fix either.
I see the good ole dealership has taken a beating in this thread, as usual, but in their defense they didn't pressure me into buying anything or using their service and they showed me the car up on the lift so I could at least see things for myself. Their suggestion of looking into a rebuild may not be that far off the total cost, given more items could be uncovered when I have the rear seal / cover gasket replaced which could bump the price up more. I understand they have their ups and downs and are not for everyone but I don't think you can tarnish them all with the same brush. That said, a second opinion is always a good idea and sometimes it's worth paying a bit more for a specialist.
Pro
Joined: May 2014
Posts: 670
Likes: 46
From: Indiana
Don't know if you've got an auto or manual tranny and I don't know about the manual but with the auto there's no need to be separating the drivetrain to do the fluid and filter change.
Le Mans Master
Joined: Jan 2009
Posts: 6,226
Likes: 33
From: Morton illinois
St. Jude Donor '14-'15
Call straightline!!! If they say 1900$ for a 10$ seal and 5 hours labor I will poop a gold brick and send it to you.
1st Gear
Joined: Jan 2016
Posts: 1
Likes: 0
You should check the torque on the oil pan bolts that go into the rear cover. Mine loosened up by themselves, causing a slight leak which looks just like a rear seal leak (I've owned since new, so hadn't been touched since the factory). These bolts are smaller than the other pan bolts, very low torque, easy to check and tighten if necessary.