2005 Buick LeSabre - Upper Intake Manifold Options for Conversion to Aluminum

[DWSTERRETT]

2005 Buick LeSabre Custom - Just purchased 65K miles.
Seems like a new car. No evidence yet of dreaded LIM or UIM leaks.
I assume I will have to do this to my 3800 at some point.
If I want to replace the UIM with an aluminum one - what are the options ?
I know the Series III will not work on Series II however will other Aluminum 3800 Manifolds from prior years (or even other models) work ?
My local pull a part has many, many cars with 3800s (Series I, II, and III) but not sure what will work.
Thanks in advance.

 

[02LTD2.0]

Your only option is to get an updated UIM. I use ATP while others use Dorman. Aluminum UIM is for Series III which use a drive-by-wire throttle body. Won't work with a Series II motor.

 

[DWSTERRETT]

None of the series I aluminum manifolds will work with series II ?

 

[02LTD2.0]

None of the series I aluminum manifolds will work with series II ?

Apples and oranges

 

[2007LucerneCXL]

A series 3 aluminum upper intake can be used on the series 2 3800, but it's not exactly a plug and play installation. Check Google as there are installation, videos and what is required to make it work.

 

[jotzgr]

Note that (at least on the LIM) 2004 and 2005 had upgraded gaskets from the factory from previous years. With that low mileage, I would just keep a watch on everything rather than replace something needlessly with parts that are of lesser quality (most everything now) than the original GM parts. I just sold a 2005 with 185K that was still on original upper and lower gaskets and upper intake manifold and had no issues whatsoever. I would recommend replacing the plastic coolant elbows and Orings with the metal ones ASAP as at this age they are hard and brittle and could break/rupture at any point in time.

 

[Buick City Bert]

While we are here, in 2010 or 2011 the 1997 Lesabre 3.8 was loosing coolant, so I watched a youtube video of a tech who tore it down to the heads in 20 minutes! It took me a little longer but while there I did the metal (aluminum) lower intake gaskets to replace the crumbled glass filled nylon ones, and put on a new "Problem Solver" upper intake manifold, that included an ingenious arrangement for the hot EGR gasses to enter the intake stream without eroding the plastic upper intake, the metal tube inside a tube worked flawlessly for over a decade of hard Northern Climate commuting, and multiple drivers, dump runs, over 150k miles without any re-occurrence of the original lost coolant issue. The newer Aluminum upper intake is a nice touch, but the aftermarket nailed it down fixing the original GF Nylon upper intake with some "fix-it" engineering.

 

[DWSTERRETT]

Thanks for the sage advice and prior experience. I have carefully filled coolant to overflow tank cold fill line and am watching it like a hawk. I also pulled plugs and borescoped cylinders and no evidence of coolant usage. Plugs look great (dark tan ) but gap had spread to 80 thou on #5. Will keep an eye on it and plan to do infamous elbows ASAP but will wait on UIM until 100K.

 

[02LTD2.0]

I'm at 180k miles on the original UIM.