Hey guys I just picked up this '96 Blazer. I have a couple questions that I wanted to come here to ask since y'all are clearly the professionals. Minus some small cosmetic flaws this thing is in pristine condition for its age and mileage (193k). The engine is nice and quiet and it shifts very smoothly. I do have a couple concerns that I want to address though.

Problem 1 - Fan noise when engine cold. I think that the fan clutch is staying engaged well past 2000rpm when first taking off while the engine is still warming up. I have a new fan clutch on the way but i wanted to ask if there is anything else that could cause this issue. It seems that once warmed up this goes away but I would like to have it fixed.

Problem 2 - Possible 4x4 trying to engage. When idling in any gear position, I have a slight rattling from underneath seemingly from the tcase. I have heard issues with these push-button 4x4 systems. What is the best way to see if my 4x4 is trying to engage? I also notice a front end gear whine when driving at higher speeds and it sounds like driving with 4hi engaged. This *shouldnt* hurt anything but my fuel economy but I would like to be able to know for sure if its just the 4x4 or possibly a blown front diff or bad wheel bearing.

Thanks in advance for any advice.

 

First off, Nice looking blazer. To be honest I don't love the body kit, but I like the graphics on the side. As far as the fan I would say the clutch is a good place to start. Have fun getting that fan off. I would look around here or check YouTube to find the best method for you.

 

I have a 2003 in the past 1996 and 1999. My clutch fan would make a big roar on start up and eventually go away when warmed up. A new clutch for the fan fixed mine. You will need a long thin special wrench to get at the fan nut and it can be hard to get off. I try to put as much tension on serpentine belt as I can to keep fan pulley from moving and whack wrench with a mallet to get shock input to break nut free. Are you confident noise is from T-case catalytic converter and exhaust heat shields have a tendency to rattle as the rust out and securing hardware loosens or is gone. Front wheel bearings would groan or moan low frequency noise, differentials would be high pitch sound. Check fluid level in front diff and look for any leakage. The front axle is engaged by a vacuum diaphragm which pulls a cable to engage a shift fork on front axle. that set up is under the battery tray and you manual pull the cable towards pass fender to engage it may be stuck partially check for free movement of cable to make sure its not partially engaged. good luck nice looking truck ! Also check tech write ups and articles on this site tons of great information.

 

Thanks, I think I did pretty good trading a '95 Del Sol for it straight up. I'm with you on the body kit. I'm planning to check and see if its rusty or anything underneath it so I could remove it. I think I would hold onto it though just in case I ever wanted to put it back on. My wife wants me to keep it on though so we will see. It wont ever go off-road on purpose so it wont hurt to leave them on. I'm getting some LED lights for it since the incandescent ones are trash. and I need to get a new grille because the front left light is pushed in and the grille is cracked (not pictured obviously, got the good side!).

I have seen one method where a guy puts a big crescent wrench on the fan nut and hits it with a hammer. I have a big 32in crescent wrench I might try that with. If I can get it off is it ok to run the engine without it on there just to see if that is what was making the noise?

 

When you say "fan noise", are you talking about a "chirp chirp chirp chirp" when you first start it up? If so that may not be the fan, but possibly the idler pulley or even the idler tensioner pulley. Either way I suggest replacing the idler pulley, the tensioner, and the serpentine belt as a matter of preventative maintenance as those are inexpensive parts that can blow out and strand you. Personally, I would replace those just to have the confidence of knowing I was running a fresh set.

With respect to the idler pulley, specifically, get one that comes with the bolt, spacer, and retaining fastener, otherwise that "chirp chirp chirp chirp" will return very quickly. I've never been pleased with any idler pulley that required reusing my old bolt/spacer. I recommend .

Can you post a picture of the engine?

 

I have had experience with GM belt tensioners before... been stranded because of it on my 2000 Silverado I used to own. Its more of a whooshing fan noise, I'm pretty sure it is the fan clutch after doing some more research.

 

The rattle is most likely the catalytic converter. They're pretty crappy on these trucks, and not only rattle when chunks break loose, they also clog.

Thankfully, they're also relatively cheap.

That truck is so 90's it's not even funny. I love it!

 

This being a first year OBDII emissions system do you think I could remove the cat entirely and put one of those little O2 sensor cats? Or will it throw codes at me?

Being born in '95 I don't remember a whole lot about the '90s but I fully experienced the cars of the '90s and this one brings back memories of getting in to my Dads similar looking '95 Ford Explorer with the sick '90s geometry paint job.

 

Very nice blazer. Looks really clean.

as for the wrench and hammer method for the fan, I personally do that everytime, cheaper then buying a wrench specifically for that... I got one that one just a little smaller(1 1/8 I think), and grinded the inside just enough that I had to tap the wrench on and off... it helps to not fly off when you swing at it... usually one good hit does it... then the same the snug it one.

for the side steps, myself to keep them I would have to find an aftermarket front and rear bumper that would go with them to keep them. If it's for the step the wife wants, could maybe find a set of nerf bars to fill in instead. Covers the gap nicely and I think they are a little more sturdier...

 

After taking that fan off one time I switched to electric fans.