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I have some ?'s

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TeamGreen Enthusiast

TeamGreen

Posted
Posted

I have an 89 GMC Sierra and am wondering if you can take out one of the rear leafsprings so the back end will sit lower? Also my truck has enough oil, but the oil pressure gauge shows no pressure when the truck is idleling. Anyone have answers?

MountaineerTom Senior Enthusiast

MountaineerTom

Posted
Posted

I don't know about the leaf springs, but I had a '91 Chevy that did the same thing once with the oil pressure.  I changed out the sending unit and it fixed it.  Mine had the 350 in it and I had to remove the distributor just to change the sending unit out.  I don't have the truck anymore, but if you need anymore help, just ask.

Hope this helps.

 

Oh yeah, welcome to the site.  

 

(Edited by MountaineerTom 99Z71 at 8:47 pm on Mar. 17, 2001)

Frank S Senior Enthusiast

Frank S

Posted
Posted

I'd be willing to bet that Tom is dead on about the gauge problem and I've also heard that you can take one leaf off of each side and your truck will still function properly.

Welcome to the site!

TeamGreen Enthusiast

TeamGreen

Posted
Posted

Thanks, I have been looking for a good GM truck message board. I will try putting in a new sending unit and see if it fixes the oil pressure prob. Which leaf should I take out if I decide to?

HiG4s Enthusiast

HiG4s

Posted
Posted

The longest one, oh wait, that's the one with the bolt holes. Ah,,, try the shortest one.

Does the Teamgreen name have anything to do with Kawaski dirt bikes?

MountaineerTom Senior Enthusiast

MountaineerTom

Posted
Posted

TeamGreen,

The only reason I needed to remove the distributor on mine was because I couldn't get a wrench on the sending unit and get enough movement on it to remove it.  Make sure you make a reference mark or something so you don't get anything out of whack.  You probably already knew that though.

76BBSub Enthusiast

76BBSub

Posted
Posted

Probably is the sending unit, and it's a pretty cheap fix, too.  The other possibility is that your main bearings are worn and you're losing pressure at idle, however, that's pretty extreme wear.  Even if they were worn you should be showing some pressure at idle, even if it's a bit too low.

Definitely start with the sending unit.

Jeff

TeamGreen Enthusiast

TeamGreen

Posted
Posted

I just started to notice that when my truck isn't at running temp yet it still has full oil pressure. Once it warms up the oil pressure goes all the way down when I stop.

JohnGMC Enthusiast

JohnGMC

Posted
Posted

Team green,your sending unit isnr behind the distributor,the 89's have it above the oil filter mount,it is easier to get to than on the 91's.I have both an 89 and a 91,GMC,s,both have had the oil sender go bad.I hope I am wrong-but it sounds to me like your oil sender is working fine,and your engine is worn out,the low oil pressure at hot idle is common when the engine gets loose.When my senders went bad,they pinned the guage as soon as you turned the key on,when it wasnt even running.replace it anyway,or put  manual guage on it,if you have less than 12psi at hot idle,its rebuild time.I would change the oil,and filter first,use at least 10w30 oil,and dont use 5w30,it is to thin for your old engine.You didnt mention how many miles are on your truck or if if the oil has been changed regularly.

76BBSub Enthusiast

76BBSub

Posted
Posted

If it is excessive wear that's causing your problem you could try running 20W-50 motor oil for awhile, but it is just a band-aid temporary repair until you get the engine rebuilt.

TeamGreen Enthusiast

TeamGreen

Posted
Posted

My truck has 104,000 miles. Do you think the engine could be worn out at this many miles. I just changed the oil and its doing the same thing. Maybe the dealer I bought it from lied to me about the miles. I don't know?

GUMPA Enthusiast

GUMPA

Posted
Posted
Quote: from TeamGreen on 5:36 pm on Mar. 17, 2001

I have an 89 GMC Sierra and am wondering if you can take out one of the rear leafsprings so the back end will sit lower? Also my truck has enough oil, but the oil pressure gauge shows no pressure when the truck is idleling. Anyone have answers?

 

 

New sending unit , then try 50w raceing oil when it gets hot out it will come up then. my 63 has 60psi at idle with HV  HP  pump. Normal chev. pressure is  low for some reason ,but it is best oiling system out there.

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