Alright so i read somewhere on the forum that the top speed of the 2003 Monte Carlo SS is around 122ish but that in overdrive it could snap the clutch shaft and the car could lose 4th gear. Now i know that somewhere along 2003 and above they started putting hardened shafts to prevent that issue. My question is how do i know if my car has it (the hardened shaft i mean)? I dont plan on going that fast but im curious to know. Thanks for any info!

 

I found out it can wear the splines over time without going that fast if it doesnt have the new shaft so now i really want to know if anyone if can help

 

I don't know much about the transmissions, but as far as "top speed", I believe GM looked it in about 105 or 110 via the PCM. The car is capable of more, but limited by the PCM settings.

 

When I was young(er) dumb(er) and full of fun; I got the 03 up over those speeds and this was still being governed...The car would hit a wall at 115mph but would just keep going...It wasn't like it killed total power, like I've experienced in other cars.

After the PCM flash or "tune" the car didn't hit that wall and just kept going....

Anyway, I've not heard of many people snapping shafts while running, they usually snap them coming off the line; at least from what I've witnessed.

You will have to upgrade your diff and diff cover to run the HD shafts, iirc....

 

Your talking about a hardened 4th gear hub. If memory serves my correct they started in 2004. My 04 had one. And yes with 4th gear only having 4fiber and 4 steels for the clutch pack 4th burns out quick if beat on. Also as you said it will strip the splines off the hub.

For what Mac is talking about is a HD diff upgrade. These are found on the supercharged cars, its a different stronger diff, diff cover to fit the HD diff, different output shaft, and different passenger side axle. Drivers axle is the same.

There is tons of upgrades for these trans but all costs big $$$

As far as snapping parts off the line that would most likely me a input shaft breaking.

 

OK so after doing more reaserch and talking to my dad who used to work for General Motors i found out that STARTING in 2003 they started putting the hardened hub and shafts so any 4T65E transmission made in 2003 and later is set to go. So thankfully no worries for me because the reason i wanted to know is because eventually (in 3-4 years) i plan on putting a comp canshaft and upgraded lifters, pushrods, rocker arms, valve springs and retainers along with a cat-back system (to add a bit of performance without putting a S/C or turbo on it but thats a different story) and i wanted to make sure the trans could hold up. But again that isnt going to be for a long while since im still a trch in training on college haha but thatnks for the help guys!!

 

I couldn't remember for sure what year, only thing is if yours was built early in 2003 the trans may have been assembled in late 2002 and not have the hardened shaft.

Also Idk what your reasons are for not going SC or turbo but engine work to these engines without a SC or turbo is pointless. You will spend a ton of money in engine parts and it will be equivelant to a stock SC car. You could do a top swap and have the same if not more power for a lot less money. Just my .02

 

Turbo Monte: Its mainly because of gas prices. High test gas is $3.97 a gallon where im from so since im still attending college and traveling 120 miles to and from school each day i cant afford that so thats why i want little upgrades like the exhaust, cams, lifters and etc. when i find a part time job ill save up for those upgrades but once i graduate and find a full time job thats when i plan on getting the S/C and installing that kit. I was planning on doing the cams and all that even if i got the supercharger but id rather lay off of that for now because of gas. Id rather give it 30-60hp for now and use regular gas and survive the school year(s) and get the rest of the power later on

 

With a good tune you can use cheap gas on a sc car. You will have moreoney in engine parts then just doing a top swap and being sc. The engine parts and labor cost will not be cheap. Also our cars only have 1 cam. Also if you get a camshaft built for an NA car it won't serve much gains on a SC build and could steal HP.

 

Not a stock cam no it wont add HP but i plan on getting a cam with higher lift points so with everything im putting in it will open the valves more and let more air and fuel in making the power stroke push the piston down harder and give the car more power. Also i wont have to pay labor because i will be doing the labor myself. Also everyone has their own oppinions on what should and shouldnt be done to a car but im choosing to do the upgrades ive described but i appreciate your oppinion.