The Blazer has a loud whine in drive and reverse but not in park or neutral. It gets louder with increased RPM when in D or R. I did a search and saw others have had this problem and there are a few YouTube videos showing the problem but there seems to be a total lack of an answer as to its cause. It is annoying and not normal. Something is on the way out but otherwise it still runs fine. A few have suggested it is the torque converter or the trans pump but no one has said I had this problem and this is what it took to cure it. The sound seems to come from the transfer case to me. Please chime in if you have an answer. Thanks.

 

I would look into the u joints first.

 

It is not the U-joints.

It does it as soon as you put it in gear when the vehicle is not even moving.

 

Well I took it up to a friends shop and he talked to a transmission specialist he knows and he told him it was the torque converter. He said it was very common. The problem is that when the torque converter goes it usually spreads its metal destruction through the trans so the trans pan was pulled and sure enough it had metal in it. If the trans pan was clean I was just going to replace the torque converter since it otherwise runs great but it isn't so I am going to replace the trans too. I don't want to remove the trans more than I have to. I am going with a GM reman as I can't find a trans shop here I trust. Having my friend slap it in is actually going to be about the same price as the cheapest shop in town here to do it and I get 5 times the warranty. It is pretty sad to me that a torque converter is only good for 178,000 km (or about 111,000 miles) in a vehicle that was never abused, never used to tow, and had regular fluid changes but what do you do. Hopefully anyone else having this problem will come across this thread and get the information they are after. Thanks to 50lb_ cat for taking a stab at the issue.

 

We picked up the Blazer on Saturday. It took 4 working days for the trans to arrive from GM. While it was there I had him replace the pitman arm, idler arm and throw on a set of 4 Firestone Destination AT's. It is at his brother's south shop today to get the wheel alignment. The Blazer is all ready for winter now and the whining noise is gone. It drives and sounds great other than the wheel is cockeyed but that will be corrected with the wheel alignment. It has been an expensive week.

 

Good to hear you got it going again. I had the torque converter go out on my work truck in under 30k and it was a brand new truck with 12 miles on it when it was turned over to me. Its got a GM 6.0 in it with whatever trans they put behind it. The guy said it was just one of those freek things that happens for no explained reason so I wouldn't hold it against your truck lol!!

 

We both like driving the Blazer so it was an easy decision to fix it. I at least "lucked out" that the trans was on sale from GM in the period that mine died. That saved me about a thousand bucks.

 

How much was the tranny from GM?

 

It was around $1633.00. The bill is at home. Regular price was around $2800.00 I believe. Keep in mind I am in Canada and we get the privilege of paying anywhere from 50% to 100% more for parts than you do in the US. The cheapest rebuild here is $2500.00 from a shop I have dealt with before (that IMO does lousy work). Most are closer to $3500.00 for a trans rebuild and all you get is a 20,000 km 1 year warranty.