# loud tapping at startup.



## 70monte (Feb 5, 2008)

I switched to 10W-30 from 5W-30 oil this past Feb in my 98 K3500 with the 7.4L. I now get a loud tapping noise at cold startup even in these 90* plus temps. I don't recall this noise with the 5W-30. Will this noise hurt anything or should I change back to 5W-30? Manufacturer recommends 5W-30 for this engine. Thanks.

Wayne


----------



## tuna (Nov 2, 2002)

Why would not just use what it calls for.Seems like a no brainer to me.


----------



## Mark13 (Dec 3, 2006)

tuna;784973 said:


> Why would not just use what it calls for.Seems like a no brainer to me.


If the truck likes 5w-30 I'd switch back to that.

My 350 has never had 5w30 in it since I got it 3yrs ago, always 10w40 in the summer and 10w30 in the winter. Zero problems so not quite sure why your 7.4 doesn't like it. What's the miles on the motor?


----------



## Milwaukee (Dec 28, 2007)

Does noise go away when it run for few mins or it continued?


----------



## sven_502 (Nov 1, 2008)

I could be wrong but I think that means a sticking lifter, which thicker oil could probably cause.


----------



## 70monte (Feb 5, 2008)

Truck has 99,500 miles on it and the reason I switched was because of a recommendation from this forum. I definetly will switch before winter. I don't know why the 7.4 doesn't seem to like the heavier weight. My 5.7L did the same thing years ago when I tried 10W-30 in it.

The tapping goes away in less than a minute and doesn't come back until the next cold start.

Wayne


----------



## Milwaukee (Dec 28, 2007)

Quick question do oil gauge show quick or it get long to get oil pressure?

What brand of oil filter you use?


Have you been change oil often or rarely?


----------



## Mark13 (Dec 3, 2006)

My 5.7 taps/knocks when it's 25 or below and my truck has sat for more then a day. Goes away a minute or two after startup. But if my truck only sits for a day or several hours when it's cold it won't do it, has to be usually 30hrs+ of sitting in the cold.


----------



## mayhem (Aug 25, 2006)

70monte;784979 said:


> Truck has 99,500 miles on it and the reason I switched was because of a recommendation from this forum. I definetly will switch before winter. I don't know why the 7.4 doesn't seem to like the heavier weight. My 5.7L did the same thing years ago when I tried 10W-30 in it.
> 
> The tapping goes away in less than a minute and doesn't come back until the next cold start.
> 
> Wayne


I'd drain it and go back to the right oil.

I missed the thread where you got the recommendation, but were you having a problem or just concerned about getting up towards 100k miles.


----------



## Mark13 (Dec 3, 2006)

I wouldn't worry about 100k on a gm motor weather it's a small block or big block. Gm builds some of the finest gas motors for truck/large suv platforms out there so 100k is nothing. I've got 172k+ on my 5.7 and she's still kickin' hard. A friend of mine pulled a 5.7 apart that had been in a 1ton dump for a landscape company, motor had 165k on it and who knows how many hours. There was no wear lip on the inside of the cylinders and the cross hatching was still clearly visible.


----------



## sven_502 (Nov 1, 2008)

Mark13;784988 said:


> I wouldn't worry about 100k on a gm motor weather it's a small block or big block. Gm builds some of the finest gas motors for truck/large suv platforms out there so 100k is nothing. I've got 172k+ on my 5.7 and she's still kickin' hard. A friend of mine pulled a 5.7 apart that had been in a 1ton dump for a landscape company, motor had 165k on it and who knows how many hours. There was no wear lip on the inside of the cylinders and the cross hatching was still clearly visible.


My neighbor ran an 88 half tonner and had 450,000 miles on the original 350 before the truck finally collapsed around it. 4 trannies, but still on the original motor. Usually they dont build a motor for 50 years if it isnt reliable lol.


----------



## 2COR517 (Oct 23, 2008)

Mark13;784975 said:


> My 350 has never had 5w30 in it since I got it 3yrs ago, always 10w40 in the summer and 10w30 in the winter. ?


You're sacrificing fuel economy running that heavier oil.

I use Valvoline Max Life synthetic blend in all my trucks. 5W-30. Tahoe has 175K, truck has 135K. The last 60K on the truck have not been easy. My truck is similar to Marks. A little noise when really cold, then goes away.


----------



## 70monte (Feb 5, 2008)

I wasn't having any issues running the 5W-30 just a little oil consumption and my oil pressure is fine. I use AC-Delco oil filters and change the oil regularly. Currently the truck has Havoline oil in it but since Walmart quit selling it and hardly any of the auto parts stores carry it around here, I switched to Valvoline conventional in my other vehicles. I did notice that my 5.7L has some startup knock using the 5W-30 Valvoline that it didn't have with the 5W-30 Havoline. I might have to find another brand to use. Any good recommendations? I will be switching back to the 5W-30 in the 7.4L.

Wayne


----------



## B&B (Nov 4, 2006)

The differences in your oil viscosity's Wayne shouldn't have created the tick your hearing, especially on a 90* day. Sounds more like an oil drain back issue or a sticky orifice valve in one of the lifters, or the brand of oil you switched to (differences in detergents between the manufactures) if this was something that surfaced suddenly.

But either way a brief tick at cold start up isn't in any way uncommon for a BB (or any engine for that matter) with 100K on the clock and won't cause any damage or issues.


----------



## RichG53 (Sep 16, 2008)

So B&B What oil weight would you recommend ??? 5W-30 or 10W-30 on an 01 6.0 Chevy!!!! Over 125,000 Miles............. I have used 5W-30 in winter months and 10W-30 in the warmer ones .....


----------



## 70monte (Feb 5, 2008)

I'm still using Havoline in the 7.4L because I bought some of the last five quart jugs before walmart quit selling it so the oil brand is the same. Nothing else has changed except the viscosity. The noise does go away so it must not be anything too serious. I may just leave the 10W-30 in until late fall and then change back to 5W-30 for the winter.

Wayne


----------



## RichG53 (Sep 16, 2008)

RichG53;785027 said:


> So B&B What oil weight would you recommend ??? 5W-30 or 10W-30 on an 01 6.0 Chevy!!!! Over 125,000 Miles............. I have used 5W-30 in winter months and 10W-30 in the warmer ones .....I use Quaker State Oil .....


----------



## B&B (Nov 4, 2006)

RichG53;785038 said:


> So B&B What oil weight would you recommend ??? 5W-30 or 10W-30 on an 01 6.0 Chevy!!!! Over 125,000 Miles............. I have used 5W-30 in winter months and 10W-30 in the warmer ones .....I use Quaker State Oil .....


Stick with what your doing Rich it's just fine.


----------

