Need help with some questions

Hey guys, I have some questions about my truck that maybe I could get some input with.

1) I recently bought a '05 QC 1500 with the HEMI and the previous owner had full synthetic oil on the engine. Should I keep the synthetic in there or switch to conventional oil? I've done my research but I'm still debating which one would work just fine versus the cost. I have a company truck so my truck I basically just use it on the weekends. (Truck has 111,000 miles)

2) When the truck is cold and I try to start it, it takes a few seconds cranking before it turns on. However, I've noticed that when the engine fully warms up, it turns on almost instantly. What might be the cause of this?

Thanks for any help folks.

Not too sure what your cold start problem is but stick with the synthetic oil. With that many miles it's better for your truck.

Gecko said:

Not too sure what your cold start problem is but stick with the synthetic oil. With that many miles it's better for your truck.

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I agree with Gecko and I'd take one step further. It's always best to stick with what your truck is broken in with. Also start using the Pennzoil ultra synthetic if you're not already. That oil is designed for our Hemi engines.

Get the battery load tested. If the battery is an original 2005 it is probably due.

to RF.

Keep in mind that when the truck is cold I would expect it may have to turn a few cycles before it starts as there could be condensation in the cylinders impairing the fire up. When the engine is warm, lighting up the fuel is much easier.

Look at your spark plugs to see if they are worn, new plugs may help. When changing your plugs (if needed) stick to standard copper core as the Hemi does not like the new alloy plugs and runs much better with copper core. Check also to see if they are fouled in any fashion which could indicate an engine condition. Normal combustion would leave a brownish/grey deposit on the plugs and all of them should be fairly uniform in wear between one another.

Cold start issues could also be due to worn ignition wiring. At over 100k miles and 10 years it is not impossible yours may be due.

With what is mentioned above and what I just added, you may be only looking at a simple tune-up to get everything back to top notch working order.

Basically just a little TLC, unless you find some real bad issue while doing the maintenance.

Not that it would have any influence on your cold start, but when I buy a used vehicle, the first thing I go through is changing ALL the fluids... Coolant, oils, etc. Old coollant can have a very adverse effect on the wear of the engine, and most people don't go through the trouble of caring for the drivetrain fluids like the tranny and differentials.

When it comes to choosing the fluid type, stick with synthetic for the engine if that is what was in the engine, and for the rest if unsure stick to the manufacturer's recommended fluid types.

You can find the service manuals in the DIY section of the 3rd Gen forum and in the maintenance section of the manual, you will find all the information on the recommended fluid type to use.

If you have any interrogation, don't hesitate to come and ask here in the forum. someone will be glad to help you out.

Hope this helps.

Thanks for the replies guys!

With regards to the oil, I'll stick with synthetic because it looks like the ideal choice.

About the cold cranking, the previous owner assured me that he had put in new plugs and had changed the oil about 2 months before, but I can't guarantee the validity of what he said. I might try to just do a tune up and probably check ignition wiring like XB said.

Everything else is working perfect, and I'm very happy with the purchase.

You might try on your next cold start to turn the ignition key on and listen to the fuel pump run for a couple of seconds. Turn the ign off and then back on and start. If the engine fires up immediately then the slow start is associated with the fuel rails losing prime.

Redtruck-VA said:

You might try on your next cold start to turn the ignition key on and listen to the fuel pump run for a couple of seconds. Turn the ign off and then back on and start. If the engine fires up immediately then the slow start is associated with the fuel rails losing prime.

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Yep, forgot that one... Good call Red

Black1500 said:

Thanks for the replies guys!

With regards to the oil, I'll stick with synthetic because it looks like the ideal choice.

About the cold cranking, the previous owner assured me that he had put in new plugs and had changed the oil about 2 months before, but I can't guarantee the validity of what he said. I might try to just do a tune up and probably check ignition wiring like XB said.

Everything else is working perfect, and I'm very happy with the purchase.

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Check the kinda of plugs he put in, and change them if they are not standard copper core plugs. You will see a big difference in both performance and gas mileage. Plus changing the plugs is not such an expensive job to deal with, even though you have 16 plugs to change.

xb1230 said:

Check the kinda of plugs he put in, and change them if they are not standard copper core plugs. You will see a big difference in both performance and gas mileage. Plus changing the plugs is not such an expensive job to deal with, even though you have 16 plugs to change.

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Okay, I'll do that then. I'll also do what Red mentioned to make sure. Sounds like a plan. I'll update you guys when I figure something out.

Single digits and teens here in PA.

Even if I don't drive the truck in a week it fires right up just like any other time. Quickly.
So, I would say if your truck doesn't it isn't "normal". Something is causing that.
I'm sure I don't have a special truck that is the only one that fires right up regardless of temp.

I agree with the fuel pump thing. Every since I had a fuel pump go out on my old 2001 Chevy I have a habit to listening every time I turn the key on to see that it comes online. Well, almost every time I guess.

And, it could be your battery. I had to replace my battery about 5 months ago and made sure I got a good one. It wasn't cheap either. But you get what you pay for. Usually.

Okay guys, sorry it took a while to update but here it goes. I did what Red mentioned and when the truck is cold, I turn the key to ON for a few seconds and then back to OFF and the truck fires up immediately.

What should be my next step? Should I be worried or this simple fix?

Thanks

The fuel pump and regulator are located inside the gas tank. The regulator is suppose to hold fuel pressure on the rail when turned off. Yours is leaking down after a bit of time. If this is only a problem when it is cold then I'd just do the double key and not worry about it. I use an external fuel regulator and it isn't designed to hold rail pressure. I have a fuel primer switch on the dash I hit a couple of times before cranking. It's all about what you are willing to deal with.