I think GM is about to phase out this engine. The car magazines claim it is outdated and rough running. Still, the people who have had it almost all praise it for durability and economy. Ran well with supercharging also. Oh, and I'll vote for PP.
Which Synthetic for 3800 Series II?
- Thread starter Striker
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Originally Posted By: Old Mustang Guy
I think GM is about to phase out this engine.
GM yet making another mistake.
I think GM is about to phase out this engine.
GM yet making another mistake.
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So what is the replacement motor ?
The Buick Lucerne is using the 3.9L version of the 60-degree engine now, instead of the venerable 3.8L.
The 3.8 had a long life, with a Series III replacement in the mid 2000's. I think it will be back, the engine has a strong pedigree of reliability and fuel economy(was great on gas). I'd take a 3.8 over the 3.5L/3.6 and 3.9 any day just because it would let me sleep better at night. And they are super easy to get HP out of for cheap!(could use my old parts on it 
).
).Mobil 1 5W30 HM oil...
Thanks for all the responses guys. In a nut shell, is Castrol Syntec 100% synthetic?
I heard about the lower intake manifold gaskets, but never heard that it was related to the dexcool but rather the material of the gaskets themselves. The new felpro units are aluminum reinforced.
The gearbox will definitely get a drain and fill with a new filter as well. Supposedly GM doesn't recommend the tranny to be flushed, but rather a simple drain with new fluid is fine.
I heard about the lower intake manifold gaskets, but never heard that it was related to the dexcool but rather the material of the gaskets themselves. The new felpro units are aluminum reinforced.
The gearbox will definitely get a drain and fill with a new filter as well. Supposedly GM doesn't recommend the tranny to be flushed, but rather a simple drain with new fluid is fine.
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I tried a couple of different synths in my gf`s 3800. Runs better with regular dino. Hers is also a high mileage one,amost 160,000 miles. It seems to run the best with Pennzoil yb 10W40. I might try Pennzoil Gold 15W40 in it next time.
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Originally Posted By: c3po
Originally Posted By: Striker
In a nut shell, is Castrol Syntec 100% synthetic?
Not exactly, it is a Group III Oil.
And Penz Platinum?
Originally Posted By: Striker
In a nut shell, is Castrol Syntec 100% synthetic?
Not exactly, it is a Group III Oil.
And Penz Platinum?
PP is mostly Group III with some PAO and possibly POE in it for correction...
Originally Posted By: Striker
Thanks for all the responses guys. In a nut shell, is Castrol Syntec 100% synthetic?
I heard about the lower intake manifold gaskets, but never heard that it was related to the dexcool but rather the material of the gaskets themselves. The new felpro units are aluminum reinforced.
The gearbox will definitely get a drain and fill with a new filter as well. Supposedly GM doesn't recommend the tranny to be flushed, but rather a simple drain with new fluid is fine.
If I understand correctly, the LIM issue was the gasket material reacting with the Dexcool, a ton of them failed. There is some debate about this depending on who you talk to, though. My bonnie was ok, but I spent an afternoon draining/flushing the whole system and replacing it with universal coolant. My tranny was acting up last year, had that hard jerk shift between all gears after a fluid/filter change. Did two more fluid changes two weeks apart, running tranny cleaners each time (TransX, and a can of B12 Chemtool for 10 minutes the day of each fluid change), tranny got a little better each time... then a final fluid change + Lucas Stop Slip. Tranny has been perfectly normal for many months now. Saved a ton of money, and I probably got lucky, but it worked. Just something to keep in mind if it happens to you after your fluid service.
Thanks for all the responses guys. In a nut shell, is Castrol Syntec 100% synthetic?
I heard about the lower intake manifold gaskets, but never heard that it was related to the dexcool but rather the material of the gaskets themselves. The new felpro units are aluminum reinforced.
The gearbox will definitely get a drain and fill with a new filter as well. Supposedly GM doesn't recommend the tranny to be flushed, but rather a simple drain with new fluid is fine.
If I understand correctly, the LIM issue was the gasket material reacting with the Dexcool, a ton of them failed. There is some debate about this depending on who you talk to, though. My bonnie was ok, but I spent an afternoon draining/flushing the whole system and replacing it with universal coolant. My tranny was acting up last year, had that hard jerk shift between all gears after a fluid/filter change. Did two more fluid changes two weeks apart, running tranny cleaners each time (TransX, and a can of B12 Chemtool for 10 minutes the day of each fluid change), tranny got a little better each time... then a final fluid change + Lucas Stop Slip. Tranny has been perfectly normal for many months now. Saved a ton of money, and I probably got lucky, but it worked. Just something to keep in mind if it happens to you after your fluid service.
Is it a major pain to convert from dexcool to conventional coolant? I'm going to have a friend of mine do it.
He will be doing the trans drain as well, would it hurt to put a can of that Lucas stuff in or should I just stick with the dexron?
He will be doing the trans drain as well, would it hurt to put a can of that Lucas stuff in or should I just stick with the dexron?
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Was the mid-80s 3800 different than the Series II 3800? I know they look alot different. The mid 80s one looks more raw,per se.
My 2001 3.8L Impala has 117,000 miles on it and has used Mobil 1 since 3,000 miles, no problems. I go 7500 miles, actually ran M1 EP 10,000 miles once.
Not my favorite car, cost me $6,000 in maintenance (most of any of my cars ever): transmission, radiator fan motor, window motor, cam and lifters (covered under warrenty), air conditioner, constant velocity joints, more
Not my favorite car, cost me $6,000 in maintenance (most of any of my cars ever): transmission, radiator fan motor, window motor, cam and lifters (covered under warrenty), air conditioner, constant velocity joints, more
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Originally Posted By: Striker
Is it a major pain to convert from dexcool to conventional coolant? I'm going to have a friend of mine do it.
I'm not sure what's involved with getting ALL of the old Dex Cool out, but I DO know you MUST get it ALL out of there!!
On some engines this involves popping out the freeze plugs, which can be a pain.
Not sure if this is the case on the Gen 2s, maybe someone who have switched one over to green/G-05/universal can chime in with info??
Is it a major pain to convert from dexcool to conventional coolant? I'm going to have a friend of mine do it.
I'm not sure what's involved with getting ALL of the old Dex Cool out, but I DO know you MUST get it ALL out of there!!
On some engines this involves popping out the freeze plugs, which can be a pain.
Not sure if this is the case on the Gen 2s, maybe someone who have switched one over to green/G-05/universal can chime in with info??
Two flushes with plain water should get 99+% of the dexcool out.
Run the engine some to circulate the water.
Empty the overflow bottle too.
Doing that IS a pain.
Run the engine some to circulate the water.
Empty the overflow bottle too.
Doing that IS a pain.
Ok i'll probably stick with the [censored] dexcool. I'll change the manifold gaskets at 60K miles anyway.
Right now I'm just trying to figure out two things.
1. which oil I should go with
2. Is there a *good additive to put in my tranny to help with longevity.
Right now I'm just trying to figure out two things.
1. which oil I should go with
2. Is there a *good additive to put in my tranny to help with longevity.
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