How big of a job is it to replace the intake manifold gasket on an LT1? What about the rear main? Are these two pretty straightforward, or should I have a mechanic do it? Any idea on how much these would cost? Thanks for any help you can give me!

 

3 to 4 hours to do the manifold. 6 to 8 hours to do the seal. At anywhere from $60 to $110 per hour. You do the math. You can call anyone in the business and ask them how long the jobs call for out of their book. And how much they charge per hour to get an accurate figure. But remember this, they are in the business to make money. More than likely your gona get the call that says "you also need" Not to mention it probably won't be done right the first time. Done yourself, you can also see other things that need attention but It aint fun in Ohio this time of year without a lift.

 

ok the second time i took of my intake manifold and had it back on again was about 45 min at the most, including cleaning it, the first time was maybe hr or two, its VERY straight forward

ps- i also dropped my tranny and did the seal by myself, with help from my brother to get the tranny out and back in, about 5 hours

 

Ok, these might be dumb questions, but I have never really done anything like this on my own. (Other than alternators, batterys, etc.) Anyways...what all tools will I need for the intake manifold job? Also...Do I just take the old gasket off and put on the new, then tighten the intake manifold back down, or do I use some kind of sealant to put on the gasket? Thanks again.

 

I use no sealant on the intake gasket. I have done it 4 times and used Felpro. Did the rear main seal. It's a job to remove the trans. Built a special fixture for the jack to remove the M6 trans. Took me 4 hours to figure out the trick to align the shaft/ clutch and bell studs. I always have problems with the front cam cover.

 

re-aligning the input shaft/bellhousing bolts is always the part that take me the longest. The second time i did it only took me about 2-3 hours, and that was all with handtools and having my car 2ft off the ground on jacks. The intake manifold is really straightforward, the hardest part about that is putting the manifold down cleanly so that you don't shimmy it around too much and smudge off the permatex or the gaskets that mount on the heads. It takes some real forearm muscle cuz the cowl of the car extends atleast 15ft.


trav

 

15 feet!!!

To put the intake back on without messing up the Permatex, just use a pencil cut in two 3 inch sections. Put them on one side (front and rear hole), and slap it down. Just did mine two nights ago, and had no problems using this method.

 

nono, i didn't do it that way cuz my plan was to mess it up atleast 2 times before i got it right...dammit, how come you never learn the tricks until 6months after i fought with it. Meh, live and learn. Plus i can use that as an excuse to why my forearms are so big, cuz it certainly isnt from any other after ours 'activity'


trav

 

Pencil method always scared me, because I was afraid of it breaking. Anyways a buddy on this board told me to use the two plastic guides that come with the oil pan gasket as studs, they screw into the holes and it works real well. And by the way, don't be confused by a couple of previous posts. You do need permatex for the intake, not on the gasket but at the front and rear of the block in between the two intake gaskets. Just run a nice bead on the block and concentrate on dropping the intake straight down on the heads. It really isn't that bad.

The rear main itself is pretty easy, it's getting the transmission out of the way. Real easy with a lift, if not then you'll definitely need a buddy, preferably a strong one. Also a couple of extensions totaling about three feet is real nice for the top bellhousing bolts. But again, nothing on any car is easy, provided you have time and the proper tools. Read this forum, buy a manual and you'll be fine, not to mention think of the confidence and sense of accomplishment that you'll get when you get it done.

Good Luck!!