1998 Chevrolet Silverado Z71 5.7 Vortec from North America


I own a 98 Silverado Z71 ext. cab, Bought it at 80,000 miles; it now has 231,000. Runs great, but starting to have issues.

Replaced fuel pump at 120k miles (still very noisy).

Rebuilt trans. at 154k.

Replaced water pump at 212k.

Just put new on ball joints and tires for the first time. That's all I've ever done to it, besides tune up and brake pads.

The issues I'm having now include loose steering, leaking radiator fluid for last year (can't find the leak), leaking oil about a quart every two to three weeks, and a snapping noise coming from underneath when the gears change, especially when slowing down then hitting the gas. U-joints are tight; not sure if it's rear end or trans., no winding or rattling noise, seems to shift fine. My air bag lights been on for 6 months.

It's been a great truck, and I plan on putting another 100k on it.

One more thing; how's every body getting 20 plus mpg? I only get 17mpg highway, and watch my gas gauge drop in town driving.

Anyone with any answers can e-mail me at stikker@ymail.com. Would greatly be appreciated.


Would you buy another car from this manufacturer? Don't Know

Review Date: 2nd October, 2010

9th Aug 2011, 19:06

Loose steering may be your idler arm worn out, it's on the passenger side; get under the truck and push up on the drag link to see if it moves, it shouldn't.

The coolant leak is probably at the rear of intake with that many miles, and the intake gaskets being old could also account for the oil loss if it's being sucked down the intake runners.

I just replaced a set that was doing both, leaking a little coolant at the rear, and when I pulled the intake, I could see where oil had been getting pulled up into the # 2 and 4 intake

runners out of the valley.

Also found 2 split fuel injector lines going to #8 and#5 cylinders.

Hope this helps, Tim.

1998 Chevrolet Silverado Z71 OffRoad from North America


Bad to the bone



General Comments:

For being a used truck, I am impressed. I am very happy with my purchase. The first Z71 I have ever owned. This is one very strong truck.

Would you buy another car from this manufacturer? Yes

Review Date: 24th August, 2010

1998 Chevrolet Silverado Z71 5.7 from North America




I just bought this truck about 2 months ago.

Replace starter at 190.000, then just replaced intake gaskets.

Now I've been chasing a water leak on the passenger side floor board when I leave it out in the rain. It leaks; anybody else had this problem with a 1998 Z71 Chev truck?

I still love my truck, 350 LT motor with 200k miles, it still runs strong, lots of take off power.

Would you buy another car from this manufacturer? Yes

Review Date: 21st February, 2010

7th Mar 2012, 18:12

I had the same problem on my 1997 Chevy Silverado 350 5.7L. I took it to several mechanics, and nobody could find out where the water was coming from.

About a year ago, I took it to have the windshield replaced. The glass technician said he couldn't replace the glass, because the cab above the passenger side was rusted. He then asked me if I would ever get water inside the cab when it would rain, and that's how I found out where the water was coming from. The rust wasn't that bad, but it was enough to let water in when it rained real hard.

13th Apr 2013, 03:12

Just bought a 1998 Z71 that had the same problem... Think it's coming in through the blower motor. Now parking it in underground. Also had the windshield replaced, so maybe it's what the other guys said? Rust or corrosion.

6th Aug 2013, 12:10

Hello there. I had the same problem. If you take the end piece off the wiper cowl, the end screw that holds the main cowl is right above air intake for the heater. Put some silicone on there and your problem will be solved.