# What's that ticking sound? **URL:** \ **Category:** Auto Type/Class\ **Tags:** trucks, gmc\ **Created:** [August 30, 2008, 4:34pm UTC](https://community.cartalk.com/t/whats-that-ticking-sound/18877 "2008-08-30T16:34:17Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![kevint](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/kevint/32/948_2.png) [@kevint](https://community.cartalk.com/u/kevint)\ **Post date:** [August 30, 2008, 4:34pm UTC](https://community.cartalk.com/t/whats-that-ticking-sound/18877/1 "2008-08-30T16:34:17Z")
I have a 1992 gmc sierra 1500.Recently i started hearing a ticking sound taht’s weirdly coming from under the truck.Could someone please help me figure out what this is. ---
**Author:** ![Roadrunner](https://avatars.discourse-cdn.com/v4/letter/r/d2c977/32.png) [@Roadrunner](https://community.cartalk.com/u/Roadrunner)\ **Post date:** [August 30, 2008, 5:06pm UTC](https://community.cartalk.com/t/whats-that-ticking-sound/18877/2 "2008-08-30T17:06:00Z")
2 or 4WD? If 4WD it could be from the front cv-joints. The noise may also come from something hanging down against a U-joint or wheel. Maybe even the brake pad wear indicator. ---
**Author:** ![kevint](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/kevint/32/948_2.png) [@kevint](https://community.cartalk.com/u/kevint)\ **Post date:** [August 30, 2008, 5:25pm UTC](https://community.cartalk.com/t/whats-that-ticking-sound/18877/3 "2008-08-30T17:25:59Z")
It’s a 2wd.I got under there cause i thoought maybe the muffler was loose and i tightned those up.Then i tightned the oil pan bolts.There’s thgis thing that spins under the truck i have no clue whta it is but i think the noise is coming from it. ---
**Author:** ![thechums](https://avatars.discourse-cdn.com/v4/letter/t/8c91f0/32.png) [@thechums](https://community.cartalk.com/u/thechums)\ **Post date:** [August 30, 2008, 10:42pm UTC](https://community.cartalk.com/t/whats-that-ticking-sound/18877/4 "2008-08-30T22:42:12Z")
If the tick frequency is always the same no matter the speed or revs, then maybe it is a bad linear transducer motor controlling the mixer door in your cooling/heating ducts. Try turning the selector knob more toward heat and see if the ticking stops.