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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: 84shortbed on March 03, 2009, 12:09:07 am

Title: just got a 90 blazer, have a strange noise
Post by: 84shortbed on March 03, 2009, 12:09:07 am
I just picked this 1990 4wd blazer up on sunday. It`s a great truck and I got a great deal. I didn`t notice anything on the test drive but now that I`m driving it more I keep hearing a strange noise when I leave from a stop. It sounds kinda like fluid moving through a hose is the best way I can explain it. The trans is a 700R4 and was rebuilt about 30k miles ago. I don`t know what transfer case I have or how many miles it has but the truck has 222,000 but doesn`t look like it. It also seems to hesitate while it`s doing this. Any ideas?
Title: Re: just got a 90 blazer, have a strange noise
Post by: Irish_Alley on March 03, 2009, 12:59:37 am
check your antifreeze if its low, about the fluids and the hesitation do a simple tune up and go from there
Title: Re: just got a 90 blazer, have a strange noise
Post by: 84shortbed on March 03, 2009, 01:04:16 am
Quote from: Irish_Alley on March 03, 2009, 12:59:37 am
check your antifreeze if its low, about the fluids and the hesitation do a simple tune up and go from there

It`s funny you say that because after it`s either coming from the trans or the a/c box. i hear it down from the floor somewhere in that area. I figured on doing a tune up and I figured that might be the problem but it ran fine yesterday on the test drive and the 140 miles home. It`s just a coincidense i guess that it happened the samae time I noticed the noise. I have tune up recods that show it had a full tune up about 8000 miles ago. I`ll check all fluid levels tomorrow. Thanks.
Title: Re: just got a 90 blazer, have a strange noise
Post by: Blazin on March 03, 2009, 04:27:02 am
Should be a NP 208 T case.
Title: Re: just got a 90 blazer, have a strange noise
Post by: Lt.Del on March 03, 2009, 09:56:27 pm
My  1991 3/4 ton 4x4 5.7 sub (http://www.delbridge.net/suburban) does that same thing.   It always has as long as I have owned it.  It doesn't bother me one bit.  I don't get the hesitation you mentioned, i doubt the problems are related. I am sure it is in the heater core area.  I know the radiator isn't quite full all the time and I beleive the radiator cap has something to do with it if the temp. spring in the cap allows too much antifreeze into the resevoir...therein lies my problem.  The plastic resevoir has a hole in it and that's why my radiator isn't full--I always have about 2 inches of air in the top of the radiator.  I assume it is the sloshing around of the antifreeze that i hear around the heater core when I turn a corner and start from a stop light or something.

My truck never runs hot because of the big radiator and oil cooler, i dont worry about it.
Title: Re: just got a 90 blazer, have a strange noise
Post by: Irish_Alley on March 04, 2009, 12:47:39 am
the cap does play a part in it if you have a higher pressure cap it takes the antifreeze to reach a higher to boil then if its a lower it boils at a lower temp