So I've got my heart set on about 10 different 2004 Monte Carlo SS's, all of them have the L67 supercharged engine. I understand the 3800 is one of GM's longest lasting engines with few mechanical problems, one of the reasons why I love it. But what about the L67? Will the supercharger cause more engine problems? Will it wear out and die sooner than the engine? I always buy a car hoping I can get it to the 200,000 mile mark, that hasn't worked so far. My '97 Sebring had a complete tranny failure at 166,000 miles, so I junked it, my '03 SS got in a wreck at 67,000 miles, it may have made the 200,000 mark. Tell me how good the L67's are on longevity, any expected problems?

 

No problems- same as any other 3800. However, the transmission can be a different story. Even on a regular 3800- I've seen some get to 200k miles, I've seen others fail just over 100k- even on a bone stock engine. Obviously a lot of that has to do with how you drive it, but some of it is just luck too- especially with the transmission.

Only added maintenance specifically on a supercharged 3800 over a regular one is changing the supercharger oil and coupler. Over time, the plastic connector that attaches the snout to the rotors (inside the case) wears out, and starts to make a rock crusher noise- rattling around. Its easy to change, you take out the fill plug for the SC oil, suck out most of the oil- and take the snout off.

Its easy to do an cheap- coupler and oil can be done for about $30 and maybe an hour's work. Other than that, its the same as any other 3800.

 

It should be fine with proper maintenance. There's a guy on clubgp.com That did a top swap on his Grand Prix GT some time ago. Now he ran a best 1/4 mile time of 11.2@120+mph and his engine has over 258,000 miles on it. He lives in Grand Rapids, MI if it really matters.

 

Wow, this is very encouraging news. I was hoping the S/C 3800 was just as reliable, seems it is. Thank you very much for your input.

 

11.2 @120 mph...must be turbo

 

Nope. Gen V M90: http://www.clubgp.com/newforum/tm.as...mode=1&smode=1

 

.....No problems yet but I only have 60k on mine. The 1st owner
took really good care of it. Changing the S/C oil is very easy
and I haven't had to change the coupler yet. You can get the
S/C oil from ZZPERFORMANCE. When you order it, order
2-4 bottles at a time. You will need to use 2 when you change
the oil out.
Hope this helps.........good luck

 

Just bought my Monte S/C here last October, it has just over 50k miles on it... how often and when do you need to change the S/C oil, as I plan on doing this soon... i also did see a great posting, it was a step by step showing of how to change the s/c coupler, pics and everything! I think it was on either ZZP or 3800performance... whoever sold the coupler had the an instruction post, GREAT info, thanks!!

P.S. any ideas on how to maintain and keep the transmission up to par? I have heard that the transmission on the 3800 can be unpredictable, and it's a HUGE job with HUGE $$$$$ to fix/rebuild.

 

....you may want to go ahead and change the S/C oil ? There is no way of knowing if the previous owner even thought about it. I changed mine with 57k on the OD. You will need to change it at least twice a year depending on how many miles and how hard you drive it.
There is a good thread on this in the How to section and 6th gen section.

 

.....Here is a link to the zzperformance web site and you see the
Oil that we're talking about .

http://www.zzperformance.com/grand_p...=154&catid=106