Hey Y'all

A little backstory first: My truck is a 2007 GMC Sierra CLassic 1500 4x4 CCSB with a 4.8L. In the fall I did Kook's 1-7/8" long tubes and catted y-pipe, an SLP blackwing and a mail order tune from Black Bear. The truck is my daily, and my pride and joy (more pics of it than my kids). I just bought an LQ4 from a guy for short money that was originally from a 2005 Silverado 3500HD with 143k on the clock. The truck was bought cheap "needing a motor", and the buyer didn't want to deal with any BS so he put a reman in it for $2200. He drove the truck for a bit before driving it straight into the shop to swap it out - no noises, engine ran great- just lights on the dash. (so I am told), then sold the other motor to me.

I got it home, threw it on a stand and took a valve cover off - nice and clean. Everything is clean so far but I haven't got a chance to go through it yet, but my intentions are to go through it and do everything BUT a full rebuild (if I can help it)- gaskets, water pump, any seals etc... a fresh coat of paint, stab a cam in it and throw it in my truck in place of the 4.8!!

I know LQ4 cylinder head questions have been beaten to death, so following my research I've decided to mill my 317's .030 to get the compression up and get them ported/polished.

I've been spec'd a 224/228 .600/.600 112 lsa bumpstick from texas speed (Gary Luther is a good guy) and also a 278mm 3000-3200 stall from Circle D.

Questions that I have:

1) I assumed getting an aftermarket cooler for my trans - any recommendations? I know I know, trans may be on borrowed time after this - I am on the lookout for a rebuildable core (4L60-65)

2) I have decided to get an oil analysis done on the motor I purchased. Is there anything else I can do to rule out any internal causes of low oil pressure without having to take it all apart?? PS I am hoping that its just a oil pressure sending unit....

3) Have any of you built up a 4L60E for a mildly hopped up LQ4? and if so, what vendor did you go through for a kit? Anything special you recommend to do while in there? side fact: I have worked in trans shops as a kid and am no stranger to opening one up- auto or manual

4) I have 3.73 gears (factory) in my truck, any concern with the factory axle in this situation?

Thanks dudes

 

I suggest doing a leak down test on the LQ4 to see what you've got to work with and you can plan based on the results the next step.

 

I would just go ahead and swap in a new oil pump & a LS2 timing chain; cheap insurance and easier to do now vs later after it's in the car. One more thing I would check is pull the rear cover off and verify that you have the oil barbell. If it's not there you'll have very low oil pressure.

 

Definitely on my radar, well except the barbell. I will check! I am going to do a leak down Saturday afternoon, then hopefully get my oil sample out.

I am going to get the aftermarket girdle for the pickup tube as well.

Any recomendations on oil pump? Should I get a high pressure Melling?

 

For what your doing a Melling 10295 pump will be fine.

I'm running the 10296 on my 403. It moves the oil very well. So much that I've added an extra quart for WOT runs, so I don't drain the pan.


As a rule of thumb, any time I get a "new" engine to me I'll always pull the pan and rotate the crank and do a look thru. You may find something that is just waiting to jump out and bite you in the ***.

 

I am intending on dropping the pan, I am also going to cut open the filter. The only thing I'd like to avoid if I can is pulling the heads. I'm still on the fence on milling them and getting a port/polish - that may be better suited for down the road when and if I need to do a full rebuild, and in that case it will be built as a 408.

I shouldn't need to get a timing set with the chain, correct?

 

Correct, just need the chain. Trickflow also sells a dampner that is easy as hell to install that helps. Runs about $45-50.

If this is just a quick rebuild get it on the road then yeah just wait. Or if you do decide to go with a 403/8 build then is when you need to decide what heads to get.

 

Ok Awesome. Thanks for the help. I am doing the leak down today since I just got myself a kit. Really anxious to see where I am at!

As far as intake, I am aware that the truck intake flows really well, so I think I am going to play that the same as heads, maybe get something fancy when I stroke it, LS6 or something aftermarket - or not?! Maybe!

 

One more thing, if you do mill down the heads, YOU REALLY NEED to remeasure the push rod length.

Compcams sells the tool for $20.

 

Yes. That has been covered when I was getting a cam spec'd. I'd go with a 7.375" pushrods in that situation, but I'd certainly measure first to be sure.

 

I am not having luck doing a good leak down with a cold engine on a stand

I think the oil analysis will give me a clue as to blow-by and bearing condition so I will see!!

Any other suggestions??

 

Got a few minutes to **** around this weekend (3 kids, pregnant wife, no time for anything lately). I pulled the drainplug and nothing. I thought it had oil in it because the end of the dip stick but I was wrong... No oil analysis. I pulled the pan, looked clean. I didn't get the chance to cut open the filter, but that is next.

I'm going to pull the heads. I'll get them cleaned up, check everything I can. If it doesn't seem doable to get this thing in my truck, it will be saved for my g-body project that I am looking to get started on in the next couple of years - after a big move (MA to TX) in 2018. Either way I will have another LQ4, just time will tell which vehicle this one is going in. If I have to do a rebuild, its getting 408 treatment. I am optimistic that this motor will work in my truck.

Any advice moving forward??