hello, im new to this forum and recently bought a used 2003 blazer Ls 4x4 from a local used car dealer.The truck is all stock, 48,000 miles, very clean in an out.My question is, my transmission shifts from 1st to second at about 3000 rpms, and when im accelerating, it sounds as if i am towing or pulling something, is this normal?I notice that there is a hitch on the truck so im assuming the previous owner towed something.It sounds like the motor is working really hard when im accelerating as if im pulling something when going from 1st to second.
Ived had many vehicles in the past and have never experienced this before?

 

Sounds like the valvebody not allowing it to shift. How is the speed does it accelerate (speed icrease as you are accelerating)? It could also be the torque converter not totally transfering the power into the transmission. Mine recently did something similar, example when I would take off or try to pass someone it reved to like 3 grandand didn't feel as though it was movingor accelerating as good as it should. I havebeen really busy and nothad time to really think about it so I posted andsome of the guys gave me reallygood starting points since I am not all that familiar with GM transmissions.Read the thread in this section titled Accelerates but won't move. I believe it was Hanr3 that told me kind of what I think yours is starting to do.
I was able to fix mine for about 50 bucks I think.The last couple of days it has run better no slip, shifts decent and has stopped whateverwas causing it . Hope this helps or a least points you in theright direction.Most of the other guys on here tend to post or be online at night time asI go toschool and workstraight midnightsso check back later. We all help each other out and if somebody has a better idea it could save you alot of money. I have been a member for like 2-3 weeks and these guys have already saved me a ton.

 

Thanks for the reply. Yes , when i accelerate, it does speed up fine, it just seems like the motor is working to hard by the way it sounds.Im not really familiar with the 4.3 vortec motor, this is my first gm truck.I did a little research on the net about gm's 4.3 vortec and some people said that its quite normal for the motor to sound like a diesle motor when you are accelerating.Is this true or not?

 

Yeah thats pretty common they sound bigger that they really are. Same here theengines and the transmissions are new to me also. I learning but slowly. I come from a Ford back round, I am very good at working on cars as I have been working on cars since I could walk, but Chevys are new to me, every auto is different even though they all work on the same pricipal. I would definately try to do what I did you never know you may get lucky. It may not work but its worth a shot. (Post: Accelerates but won't move). You could possible have begining sypmtoms of what mine did. I was so fretting the converter or trans, still may have to replace but for now it has taken car of it. Even the most experienced still ask question and these guy have been very nice and very helpful. Also its kind of hard to describe over the internet what a vehicle is doing that while sometimes its hard to understand what people are getting at, in different parts of the country or the way other people may have learned it makes is sound weird. Any assistance you give us is also greatly appreciated! I don't know how to do the whole picture thing hoping to have somebody show me how since I am relatively new to the internet. My current project is my buddies car its almost complete so hopefully one day I can put some pictures up. (64 Ford FairlaneThunderbolt Clone with 427). This car is equip with a period correct rollbar, lap belt. White Paint with original style super stock reproduced decals.
The only difference is the rear end is a Strange unit built to handle the power, 2 spd. Power Glide and othergoodies to helpthe 427 which instead of 425 hp like the original it will have about 750 hp to the wheels without a power adder.

 

Thanks for the insight. I am also from a ford background for trucks. I recently sold my sportrac and was just driving my summer car(1995 camaro z28)for the last six months and recently bought this blazer for my dd and more so , my winter vehicle as we get allot of snow where i live in the winter.
Yes, the 4.3 vortec sounds allot bigger than it actually is.Well i thought maybe it wasnt in od, ut i looked and cant see the overdrive button anywhere for my 03 blazer. Im wondering if itIs even a 4 spd auto with overdrive?
Well i have some peace of mind as the truck is still under warranty so if it is something big, at least its under warranty.

 

Yeah it has overdrive (thats what the D is). It is PRND321, the 3 is like the non-overdrive tow-haul mode. Snow sounds awsome I live in the midwest and we haven't had hardly any snow in the last 2-3 years. Luck on that one with the warranty when I got mine it had like a 100,000 on it and within a week the fuel pump went. After two years I am up to 5-6 thousand in repairs see that list at the bottom of my box that used to be my soon to be added now it is just a wish list as I already have some of the parts but not the money to finish things need to install the parts. Take a look at the post in the lounge titled should I buy a high mileage 95 4x4 and read my post #7 for the updated list of parts I've replaced. My parents and friends think I am crazy to continue putting more money into it but the fact that I love my truck, in my opinion it has been my best offroad vehicle even being mostly stock. I decided I am just going to stick it out till I can afford to modify and turn it into something I can be proud of. With the addition of two broken feet which are healing it has slowed the process some. Gotta love the fact that I am still offroading. Keep working at it, it will come around. My favorite quote which keeps me going is in a Jonny Lang song and its A Quitter Never Wins.

 

Mna that sure sucks, 5 - 6000 in repairs in the last two years, i sure fell sorry for ya.Hopefully that is it for repairs.In the future id like to add a lift also with some bigger tires, but for now all my $ in the last 6 months went into my z28 for repairs. I spent almost 5000 in repairs so i know how you feel.
ya, we do get allot of snow here in the winter.Sometimes we get dumped on pretty good, so if you dont have a 4x4, you wont be able to go allot of places till they plow, unless you have a 4x4.I live in winnipeg,manitoba, Canada.Are you familiar with canada at all?

 

Not really I can't stand the cold weather Ijust likesnow.I have to say my first experience withCanadawas watching ice road truckers.My girlfriend and I like Hugh the best.

 

Ya, i hate the cold weather. it gets super cold in my city in the winter. Sometimes minus 40.

 

Does anyone else have any input on this one?It would be greatly appreciated.