2004 GP GT 3.8L (L26) replacing Lims

[brianwalter86]

I just had a few questions on replacing the lower intake manifold gasket.
What all gaskets should I replace while doing the job?

This is the list I gathered
-uim gasket
-lim gasket
-valve cover gaskets
-change thermostat and gasket
-flush coolent system and swap dexcool with prestone any color antifreeze
-change plugs

Should the oil be changed when completed?

I found there is 2 prices for lims gasket. $40 and a $75 one. Both made by same company at autozone.

Should I just go all out and buy the more expensive because they say its better?

Also I was looking at prices I can get a upper gasket set for $189, it has all gaskets I need and its comes witbh the better gaskets and some o rings for fuel injectors and extras.

Or would the list I made cover what I need.

Would I use any RTV silicone for this project? If so where?

Is there a guide I can look at and follow? I got some info from autozone but all it say is take all these parts off and reinstall them in a order they list. So i it doesn't have any detail.

You know if I should use the prestone any or switch to green stuff? I just know I don't want the green to gum up if there is some dexcool left.

Thanks for reading and for any infomation you can give.

[GtpKo]

Make sure you get the aluminum gaskets, not the plastic ones. Don't skimp on the LIM gasket, a measly $20-$35 extra is worth it. You'll need coolant elbows too.

http://www.grandprixforums.net/lim_lifter_video.php
This is a cool vid that covers alot. It's on an L67, but still very useful indeed.

[L36pro]

get the cheapie. the cheaper one is felpro. the more expensive one is a vender direct part which costs more because the price is dictated by the vendor and not by autozone. trust me, i work at autozone and had to make the same decision when i did my LIM about a month ago.
unless the more expensive one is aluminum, which i doubt.
theres no better gasket than felpro.... for the money.

[Fivefingerdeathpunch]

the better gaskets are aluminum and you want them so they never have the issue again.

But it can be said that you might not have an issue with the plastic one.

[L36pro]

yeah, aluminum are much better. but i dont think that the more expensive one is aluminum. im pretty sure its just Vendor direct. ill check when i go in to work tomorrow.

[BillBoost37]

GM Aluminum gaskets. I've used all of the various ones. Do you want the best gasket you can get? GM, next best is the Fel Pro with teh T on the end for the metal frames.

UIM, do this gasket as well. Although it likely could be reused.
Throttle body, clean this while you have the pieces off.
Injector 0-rings
Coolant elbows
Valve covers (only if leaking)
Thermostat and gasket. (Is yours bad? extra work and money for something that isn't a problem)
Coolant flush (it's probably time to maintain it...it's past the 5 years/150K miles right?)

Oil change. As long as you don't dump coolant into the motor when you open it up, start the car afterwards and let it run for about a minute. Then change the oil.. This will flush any junk out. If you get a lot of coolant in it.. dump a couple quarts through with the pan bolt out. Then change it as many times as it takes to ensure there is no coolant left in the crankcase.

[brianwalter86]

Thanks guys for your responses.
Billboost you say to replace coolent elbows, where are they located?
Just curious anyone know how long this takes to do?
Anyone use rtv silicone foranything on the job? Just want to make sure I got everything before I start and won't have to make any extra trips.
I see someone posted aboug replacing fuel injector o rings,
Should I just buy the whole upper gasket kit for $189? Includes head gasket too whcih I will not use, lim,uim,valve covers,injecctor o rings, thernostat gasket, and a bunch other odd and ends.
If I buy gaskets seperate it only cost like $132, that's with cheap gasket.
And if I buy them seperate with the expensive gasket it would be $167

Once again thanks guys

[L36pro]

coolant elbos are really easy. we sell them at autozone in the help section. pull the alternator bracket, then the water pump housing. they come out nice and easy. ive found that the hotter your 3.8 runs, the faster you have to replace them. ive got a 04 bonneville that needed them at 70,000 miles, but my gt runs real cold and has 212,000 and didnt need them. i replaced them for the heck of it.
when doing anything with orange gaskets/o-rings, make sure that after your torque everything down, run it for a day, then retorque everything once more. the orange colored o-rings and gaskets are heat activated to form a tight seal. they reform, flatten out, and need retorqued. if you fail to do this, you will leak vacuum, coolant, or both.
if you plan on using the upper gasket kit, buy it. if not save your money and replace things as they come. you dont need to take off the valve covers for the install.
during the LIM wash down the valley pan with oil to get the gunk out, and try and clean the water jackets in the heads and get all the deathcool gunk out. brake cleaner comes in handy for cleaning stuff, and it evaporates quickly. and the LIM gasket you get should come with a small container of rtv. more than enough to do the job.
if your gonna put a new thermostat, go to autozone and get the failsafe, which will ensure that your ride will never overheat again due to a thermostat failure. they dont fail closed, they fail open if they go bad.

[OH4CompG]

Since no one answered about where to use rtv.... When you put the new LIM gaskets in place, you want to use RTV on the corners where the side gaskets meet the front and back gaskets. A dab under and over the joint will be just fine.

[L36pro]

yeah, it just seals the 4 gasket pieces together at each corner. make sure you get the LIM on before the RTV starts to harden, because it will leak.

[brianwalter86]

Thanks guys for all the info. I found out the cheap manifold gasket is plasstic so ill buy the expensive one.

Anyone have an idea how long this takes to change all of these?
I do have a leaky valve cover gaskets. Also have leaky thernostat gasket.
Niether is leaking bad but it has residue near them. Figured I would replace them.

Thanks again

[L36pro]

took me 2.5 hours in the rain. it sucked, but i knew what i was doing because i had done about 10 UIM's.
put a new therm gasket in it. doing a radiator flush wouldnt hurt either.

[matt5112]

the $75 gasket is more likely than not the felpro permadry plus, second design, which is the only aftermarket gasket you should buy.

[brianwalter86]

I watched that video of the lim and lifter replacement. it was very helpful.
it did bring a question to mind though. he use lock tight for his intake manifold bolts. did he use them for the intake plenum bolts also?

i seen some posts about people putting lower temp thermostats in there 3.8. like a 185, would anyone suggest that or stick with original?

[L36pro]

dont use locktite on your manifold bolts. the orange gasket stuff will flatten out after the engine gets hot and the bolts will need retorqued. if you use loctite, youll just have to mess them up when you retorque everything again. what I used in my bolts was neverseize.

[blueguy]

Why would you put Anti-Seize on bolts that only get Torqued to 12 ft. lbs.? Unless your about as strong as the common house fly.

[matt5112]

You're supposed to use thread sealant.

[blueguy]

As in GM PFTE Paste...no Anti-Seize. This kid is just grabbing stuff off the shelf to help the stores check out challenge scores.

[L36pro]

i used anti sieze on the IM bolts on my buick 455...... itll rofl stomp your gtp.

[TheOtherNick]

lol having to retorque loctited bolts, thats the purpose of loctitie to keep them where they are.