I would have to wash up if I go inside and open the shop manual. I have two bags of bolts, 10 in each. One set has 10 mm heads, the other has 13 mm. Which are for the valley cover and which are for the timing cover?
Thanks, I will drink beer and wait for the answer.

 

Pretty sure the 10mm are the vally cover.

But I think some motors use 10mm on the timing cover aswell.

 

Hmm. I ended up opening the book. I forgot that I have to go inside to use the bathroom. The book doesn't tell you. Thanks for the quick reply.

 

I thought the 04/05 up motors had the bigger valley cover bolts.

My timing cover and valley cover (02 motor) are definitely 10mm

 

Good answer. I have the newer cover with the breather built in. Thanks.

 

The front and rear timing covers have a 10MM head on all years.

The Early motors had the same 10mm heads on the top valley cover.
The Later motors used a larger 13mm head on the top valley cover.

 

Thanks.

 

Yes this, I have mine apart right now and timing is 10mm. I have a different valley but my stocker has 13mm bolts.

 

Timing cover has 10mm bolts on every year model. In late 04 they started with 13mm valley cover bolts. My 08 5.3 had 13mm rear cover bolts as well