redriver racing

Here is the deal 5.3 120,000 miles. Lifters come apart, replaced cam, lifters and oil pump. Truck has never had good oil pressure before this. Was within GM spec. So put another oil pump and new o-ring just to see what would happen. Nothing changed. Checked the pressure @ the filter and had about 30psi cold, engine warm went down to about 15ish. This is with a mechanical gauge. Then checked oil pressure at the sending unit with a mechanical gauge and found oil pressure @ 20psi cold but when it idles for 15 to 20 minutes it will drop to about 0-6psi. The mechanical gauge will show close to 0 sometimes. U can drive it and it will hold around 20psi but if it idles it close to 0. When checking pressure @ the filter it would never drop below 15psi. Why is there a drop between the filter and the sending unit?? Removed the oil pan and found nothing blocking the pickup tube.The truck has some oil pressure but not very much. Could cam bearings cause this?? (Yes, it is full of oil.)

IDRIVEAG8GT

Uhhhh.... Was this once a DoD engine? If it was, and you converted to non DoD and didn't replace the valley cover with non DoD style, you're not gonna have jack **** for oil pressure.

If otherwise, you've got a spun rod/main bearing, oil restrictor broken, or pushed out, etc etc.

cabel1

iTrader: (3)

If it was DOD the pressure relief in the pan could be stuck open.

redriver racing

It is a DOD engine and the valley cover has been replaced. Everything is stock. I have put about 250 miles on it so I don't think its a rod or main bearing.

IDRIVEAG8GT

You made sure to put the rubber seals in the DoD plate when it was installed?

redriver racing

The DOD plate come assembled, new from GM. I went and had the DOD turned off yesterday. I called to double ck the parts I got to make sure they were all right and found the lifters r wrong. They don't have the springs coming out of the top like the old one did there just regular lifters. They were comp lifters so did not think much about it. So going to do a complete DOD delete and see if that fixes it.

the450r

iTrader: (1)

i have a 03 silverado doing the same thing. tried a o ring and no change. disassembled pump and everything looks fine. its a LQ4 6.0 non DoD does have an oil cooler.. oil pressure fluctuates cold or hot. 30 @ 2k. and at idle 25-10 then goes 10-0 and back. and there is no engine noise.
only thing i can think of is the oil barbell plug at the back of the oil galley behind the rear cover.
is this the oil restrictor?

87chev4x4

I have an 07 pickup with a dod 5.3 with 89000 on it. It uses 1qt oil for every 1500 miles I notice no smoke at start no leaks! Where is it going? And I would like to ride myself of the dod what is the parts list for this and what would be a good cam if I am going to be in this far? Thanks guys

the450r

iTrader: (1)

found the cause after posting. front main bearing spun and was seized to the crank. i cant believe it didnt make any noise at all.

redriver racing

Still have not changed the DOD plate yet will have it changed one day next week and we will see..

IDRIVEAG8GT

I'm still a little confused. You cannot.simply cannot run a non DoD engine, with a DoD valley cover. You won't have oil pressure. You're gonna spin bearings or do serious damage to that engine.

cam75w/ls1

iTrader: (2)

I recently worked on a 08 Tahoe w/ a 5.3 and had zero presssure at the sending unit. Found a TSB about the filter under the sending unit on the VVts. Yes there is a replaceable filter inside the hole where the sending unit screws in. I replaced it and BAM! Had oil pressure on the instrument cluster again. Hope this helps.

redriver racing

The motor is a DOD engine but what i want to do change the Valley cover to a non DOD. Does anybody no the part# to the cover that will work or do just drill and plug the holes in the block?? What will be the best thing to do?

redriver racing

We have good oil pressure now!! What had happen was they sent me the non DOD lifters and i just was not paying attention. So i went and had the DOD turned off. Then got me a LS2 valley cover and it fixed my problem.

j.washburn

I have a 07 silverado 5.3 afm one of my lifter was making horrible racket tore it down and sure enough a lifter ground a groove in my cam. I ordered everything to delete dod and i have a ls3 cam and valve springs i'm gonna throw in there "has anyone tried this?" I noticed on the front cam bearing there was a small rough spot on it is this somthing to worry about? The cam i took out other than the one lifter groove it looked and mic'd good should i just throw everything in there and ride it out? it has 145000 miles on it. how hard is it to replace cam bearings?

av08

So can you please give us more detail on the job to delete AFM (DOD), part numbers ....did you change the oil pump &camshaft?

Because of the cold-start tick, I had all lifters (16) and camshaft replaced, noise is a lot better but still there, but the oil pressure drops to about 19-20 at hot idle after the repair. Before the repair the it idled around 40 PSI.

Great post.

redriver racing

Yes, oil pump, lifters and cam were replaced. I used the stock cam, stock oil pump. The lifters were a set of comp 5.3 replacement lifters but they were for a non DOD motor. The valley cover i used was GM Part # 12575742 $175.83. Just bolted on and no modification!!! Had the DOD turned off and know ck engine light.

j.washburn

Thunderracing.com sells a dod delete kit it includes the valley cover lifter trays ls7 lifters gm head bolts and gm mls head gaskets for $350 http://www.thunderracing.com/shop-by...T.-and-D.O.D./ Or you can order the parts from gmpartsdirect.com a little cheaper. I got all of mine from thunder racing it was on my doorstep in 2 days.

redriver racing

That looks like a pretty good deal, Thank's. The only problem i have had was it through some oil pressure code but it has only did it once.

mrhotrod69

hey I would like to ask you all a ? I just put an 08 truck 5.3 with dod in a chevelle i changed intake to a corvette style and also changed lifter plate and intsalled new orings when i cranked it it ran great for about 20 secs then made bad noise under intake i changed lifter plate back to the dod plate but its not pluged up great oil pressure and runs perfect will it be ok?