Ticking Nightmare on 2001 Tahoe 5.3

[tadv]

So for the past few weeks me and my dad have been trying to fix a tick that just started on my 2001 Tahoe LT 5.3L. Through all manner of twists and turns we finally managed to replace the lifters and get everything back together and running again, but the tick persists!!! After hearing from a mechanic friend that my camshaft is likely worn out I turned to ChatGPT and fed it as much info about the issue including all the parts we swapped in, and this is what it fed me:

You recently replaced the lifters in your 2001 Chevy Tahoe with BTR Delphi LS7 Hydraulic Roller Lifters (X12499225-16). However, you kept the stock pushrods (7.400" length), and now you’re hearing a distinct ticking noise that gets louder once the engine warms up. The oil pressure is fine, staying around 50-60 psi, so that’s not the problem. What’s Going On: The LS7 lifters you installed actually require slightly longer pushrods (~7.425" to 7.450"). Since you reused the stock pushrods, there isn’t enough preload on the lifters, which is why they’re ticking when the engine gets hot.Should You Keep Driving It? Right now, the ticking is mostly annoying, but if you keep driving with the wrong pushrod length, it could cause serious damage to the lifters, pushrods, rocker arms, and even the camshaft over time. If you’re driving gently, you’re probably okay for now, but if you keep driving hard or towing, you’re risking bigger issues. What You Need to Do: To fix this, you’ll need to replace the stock pushrods with 7.450" hardened pushrods (like the BTR BTC-PR7450312-16 set). This will restore the correct preload and eliminate the ticking noise. After that, just make sure to torque everything properly, and your engine should run a lot smoother. Bottom Line: The ticking is happening because the stock pushrods are too short for the new LS7 lifters. Replacing them with the correct pushrods will fix the ticking and prevent future damage.

How accurate does this sound? I'm not really sure how to properly fact-check this so hoping to get some input from people much more experienced with these engines than myself.

 

[justirv]

So for the past few weeks me and my dad have been trying to fix a tick that just started on my 2001 Tahoe LT 5.3L. Through all manner of twists and turns we finally managed to replace the lifters and get everything back together and running again, but the tick persists!!! After hearing from a mechanic friend that my camshaft is likely worn out I turned to ChatGPT and fed it as much info about the issue including all the parts we swapped in, and this is what it fed me:

You recently replaced the lifters in your 2001 Chevy Tahoe with BTR Delphi LS7 Hydraulic Roller Lifters (X12499225-16). However, you kept the stock pushrods (7.400" length), and now you’re hearing a distinct ticking noise that gets louder once the engine warms up. The oil pressure is fine, staying around 50-60 psi, so that’s not the problem. What’s Going On: The LS7 lifters you installed actually require slightly longer pushrods (~7.425" to 7.450"). Since you reused the stock pushrods, there isn’t enough preload on the lifters, which is why they’re ticking when the engine gets hot.Should You Keep Driving It? Right now, the ticking is mostly annoying, but if you keep driving with the wrong pushrod length, it could cause serious damage to the lifters, pushrods, rocker arms, and even the camshaft over time. If you’re driving gently, you’re probably okay for now, but if you keep driving hard or towing, you’re risking bigger issues. What You Need to Do: To fix this, you’ll need to replace the stock pushrods with 7.450" hardened pushrods (like the BTR BTC-PR7450312-16 set). This will restore the correct preload and eliminate the ticking noise. After that, just make sure to torque everything properly, and your engine should run a lot smoother. Bottom Line: The ticking is happening because the stock pushrods are too short for the new LS7 lifters. Replacing them with the correct pushrods will fix the ticking and prevent future damage.

How accurate does this sound? I'm not really sure how to properly fact-check this so hoping to get some input from people much more experienced with these engines than myself.

You can purchase a pushrod length checker for confirmation of the exact length you need. On the other hand, these are famous for exhaust manifold leaks, from broken bolts, etc. May sound like ticking.

 

[tadv]

You can purchase a pushrod length checker for confirmation of the exact length you need. On the other hand, these are famous for exhaust manifold leaks, from broken bolts, etc. May sound like ticking.

Positive it's not a manifold leak. Ive had one for a while and only recently did this new tick start. Very different noise and coming from the passenger side of the engine where all the bolts are intact.

 

[justirv]

Positive it's not a manifold leak. Ive had one for a while and only recently did this new tick start. Very different noise and coming from the passenger side of the engine where all the bolts are intact.

Well I'm not qualified to argue with the answer you had posted. If that were the case, I would think that the ticking would be on both sides of the block. I like your parts selection so far. You could measure your rocker movement to verify cam lobe wear. For piece of mind, the pushrod length checker may be a cheap solution. https://www.summitracing.com/parts/tfs-9501

 

[justirv]

Well I'm not qualified to argue with the answer you had posted. If that were the case, I would think that the ticking would be on both sides of the block. I like your parts selection so far. You could measure your rocker movement to verify cam lobe wear. For piece of mind, the pushrod length checker may be a cheap solution. https://www.summitracing.com/parts/tfs-9501

I retract the "both sides" comment, one bad lobe could cause it with that thought. You may be able to feel lack of tension (while spinning it) on the pushrod(s) affected. Measuring rocker deflection (micrometer) will give a good indication of abnormal lobes.