Newbie here...

After years of owing primarily Toyotas, I find myself to be the proud owner of a new-to-me 2003 LeSabre! This is my first GM car, since a family member owing a 1986 Pontiac 6000 in the early 90s.

My "new" car has less than 60,000 miles, having been owned previously by the an elderly owner since new.

I've read up on the various common issues and quirks, and have come up with the following list of item to fix or upgrade. In descending order of urgency; I will begin the process of fixing each of these items.

I am looking for input as to how to best do this, with recommendations for the "right" parts (my current choice in blue, other option in red). My philosophy has always been to fix it right - fix it once, with the best available parts possible.

My short wishlist of improvements include:

1) Replace the original upper intake manifold (ATP Automotive Graywerks 106001 or Dorman 615-180) and the lower intake manifold gasket (Felpro MS 98014 T or ACDelco 89017816 )

2) Flushing the Dex-Cool and replacing with something else (though I have no idea what would be ideal);

3) Install front and rear sway bars from a Bonneville SSEi, or Cadillac Seville STS; with regards to the rears, my choices are any of the 18mm (20757300) , 20mm (25650388) , or 22mm (25666234). I am honestly not sure how much of a difference the different sizes will make, so any input would be valued. As GM no longer sells these parts directly, I have to rely on either secondary vendors, or the junk yard. Sadly, the local Pick-and-Pulls in my neck of the woods just closed down, and I don't feel like getting fleeced by a wrecker (who have on numerous occasions asked for MORE than new parts from the dealership!)

4)Upgrading the 11″ rotors and brakes to equivalent 12” units from the dozens of GMs of that vintage, sporting the larger set-up (the current stock set up is functional, but a bit squishy). Alternately, would better brake pads on the current 11" rotors be sufficient? The brakes feel VERY squishy, though stopping distance seems to be decent.

5) Replacing the ATF with Amsoil or similiar, and installing an auxillary cooler;

6) Replacing the auto-leveling rear shocks with a Monroe conversion kit (Monroe 90007)

These are the things right off the top of my head. Any other ways to improve upon an otherwise pristine (and bone stock) vehicle? Hopefully with the very modest suspension upgrades,handling will improve, while preserving the “Buickness” of the car?

Any constructive input welcome! This will be a long-term project, as I have something else as a daily driver.

 

Pretty ambitious schedule. My Lesabre is a few years older and just turned 50k miles. So far I have done upper intake(ATP) lower intake gasket( felpro metal) and replaced the lower intake manifold because of excessive pitting, OEM stat and also those pesky plastic coolant elbows with the Dorman aluminum ones.. Refilled with new Dexcool/ distilled water. I am not convinced that Dexcool is bad in a properly maintained system. Added a Hayden transmission cooler and refilled transmission with Dexron 6. No further upgrades for me unless something goes bad. So for the most part, we are on the same page. You probably have air in your brake system causing the soft pedal. Don't think 12 in brakes are needed unless you plan on going down Pikes Peak.Also suggest getting this inexpensive part for your 4T65E transmssion.
http://shop.tripleedgeperformance.co...?categoryId=-1

Good luck with your projects.

 

Hi Krankshaft, Thanks for the tip on the lube tube retainer... didn't realize that was an issue.

After sourcing all the parts from Amazon, I've now essentially performed all of the maintenance/improvements set out in your post, except the transmission cooler. In the end, I questioned my ability to do a proper flush of the coolant system, and erred on the side of caution, by simply doing a Dex-Cool drain-and-fill (using Long Life Prestone Dex-Cool compatible fluid).

I have some experience with these, on account of having installed a Tru-Cool unit on our minivan. Have you noticed any noticeable difference with your install of the transmission cooler on the LeSabre?

Am I correct that this is generally a pretty basic (and reliable) transmission? I am thinking of simply changing the fluid to synthetic ATF, and installing an aftermarket drain pain with an integrated drain plug, rather than installing a cooler. I figure that the synthetic fluid should help to lower operating temperature, and regular (annual) drain-and-fills would suffice. The cooler is still an option, but unless there is real improvement, adding an other component to the system (even if it is a relatively simple install) adds another area for potential problems in the future.