Needing some opinions, here’s what’s up. My 2000 just rolled over 300K, everything that has ever even thought about needing to be replaced has been with oem or better parts. I’m on the original injectors, original VP44, original head gasket, and original turbo. My Tappet cover is leaking pretty bad, and aside from that leak I’ve not had any leaks other than a little weeping at the oil pan. My question is, should I just do the Tappet cover and keep going, or should I go ahead and do injectors, VP, oil pan gasket, new turbo, rebuild vacuum pump, front main seal, ect while I’ve got everything pulled apart. I am usually a “it ain’t broke” kinda guy, but at 300K I have to consider these things will likely need to be done sooner than later.

19 hours ago, Andyba20 said:

I’m on the original injectors

Personally don't drive till the injectors are replaced. Injectors should be replaced every 100k - 150k miles. You are playing with fire.

 

19 hours ago, Andyba20 said:

original head gasket

Head will develop what's called head curl typically around 300k to 350k miles this could be stopped if you ditched the stock head bolts and installed ARP suds. Remember Cummins head gaskets are not made by Cummins but by BLK out of China.

 

19 hours ago, Andyba20 said:

My Tappet cover is leaking pretty bad,

Replace the gasket but do it right and remove the VP44 so as to get the cover out and in without making a mess of the gasket and being able to clean the block face well. No sealants! No Silicone!

 

19 hours ago, Andyba20 said:

oil pan gasket

The oil Pan gasket is super easy and takes me about 2 hours to do. It is required to lift the engine and also jack up the truck so the front axle hangs. The oil pan can slip right out without any problems.

 

20 hours ago, Andyba20 said:

new turbo

Why? I'm still running my HX35W with +150 HP injectors and no issues with EGT's or MPG's at all. Tuning will allow you to go much farther with the stock turbo keeping spool up times short. 

 

20 hours ago, Andyba20 said:

vacuum pump

Vacuum pump rebuild kits are super cheap and can be purchased through Cummins. Takes about an hour to replace the seals in the vacuum pump. 

 

I've got articles for most of this work just check out the article database. 

If you're pulling the valve cover, you might as well do the injectors as they have to be WAY out of spec with that many original miles. If your content with "stockish" power (no desire for bigger turbo/tuner etc), it would be a great time to upgrade those injectors to RV275's. They are real close to the cost of stock injectors but will give you a bit of a bump in power with no need for other upgrades. Check DAP for some Rv275'/50hp injectors as they have decent prices and really good injectors. 

 

Its also a great time to pull the turbo and spend about 75.00 on a rebuild kit. There are a few decent youtube videos showing how its done. 

@Mopar1973Man I did ARP studs about 10K ago, I’ve got infinite injectors, a turbo labs rebuild kit and Napa vacuum pump rebuild kit sitting in the shop. Only reason I haven’t done any of that yet it bc everything is running really good. I’m getting 8%-10% engine load at idle. 
 

@5akman I’m with you and Mike, the injectors are a no brainer, I guess the biggest question in my mind is how much longer will I get out of the 300K mile 24 year old VP44. Wondering if I should just proactively get a new one, or see how far I can go. 

Do some research before buying a VP. It seems like there are very few shops with the test equipment needed to do a fool proof rebuild. I only have 85k on my '01 and I'm wondering what big ticket item will fail first and  when it does, I'm sure it will be based on the age of the rig and not the miles . I'm hoping the VP holds out for many more years

On 10/11/2023 at 12:26 PM, Andyba20 said:

I’m on the original injectors, original VP44, original head gasket, and original turbo.

 

I am in a similar situation.  I am at 382,000 miles on my truck.  New RV275 injectors at 303,000 miles.  Rebuilt VP44 at 87,000 miles, currently 295,000 miles on the replacement VP44 with no issues.  Turbo is still original.

 

Personally, I would never replace injectors at 100,000 miles, but at 300,000 miles your injectors have served you well, so it is time to replace them.   On my truck before replacing injectors at 303,000 miles, the engine still idled smooth, power was good and fuel economy was good - probably like yours. 

 

I plan on running my VP44 until I start seeing something that warrants replacing it.  Same goes for the turbo.  Usually, symptoms will show if a problem is starts occurring with either the VP44 or turbo - not likely to leave you stranded.  And, the turbo is easy to inspect for any rubbing that may begin to occur.

 

I have plenty of oil leaks to find and I am just going to tackle them one by one.  I have already replaced the tappet cover gasket - good to follow MoparMan's advice regarding no sealants.

 

As far as the head gasket, I will wait until I can schedule some down time, so I am not rushed.

 

A couple of years ago when I was performing fuel return flow tests from the VP44, I installed a fuel line bypass (with a one-way check valve) around the frame-mounted lift pump.  After testing was completed, I kept that bypass in place in case of a future lift pump failure.   With the bypass in operation I would still be able to drive the truck home without a functional e lift pump. 

 

- John

Good stuff @Tractorman, gotta think through these things, especially with winter coming…my tolerance for wrenching outside in a cold garage ends in about mid December, so trying to use the mild weather now to get some things done. The HX35W has worked great for me, but I’m considering having Savage Fab build me a turbo. We talked and he said he could build be an he351cw with an HX35 comp cover for $1000. I think that would be the perfect turbo for my needs (mountain towing, 350hp, 3.55 gears). Slight boost at cruise which is what I need since all the roads here in Tennessee are up and down over and over. I have weston schupe 7x.010’s on the shelf but I think I’ll try the new quadzilla 50s or 75s instead, just in case my Quadzilla ever dies, I’d rather limp home with a smaller injector. I think doing the Tappet and oil pan will fix all my leaks for now. 

On 10/13/2023 at 11:58 PM, Andyba20 said:

The HX35W has worked great for me, but I’m considering having Savage Fab build me a turbo. We talked and he said he could build be an he351cw with an HX35 comp cover for $1000. I think that would be the perfect turbo for my needs (mountain towing, 350hp, 3.55 gears).

 

Food for thought...

 

Beast my 2002 Dodge is roughly 500 HP with +150HP injectors (7 x 0.010 popped at 320 bar) and still running a HX35W turbo (54/60/12). My last haul I did was pulling my 31-foot RV back from Parma ID and I would just set the cruise and go for it. Even climbing 7% grades on Highway 95 I was hard-pressed to even get over 1,100*F. I'm also running 3.55 gears but after changing from 265/75 R16 (31.6 inch tire) to 245/75 R16 (30.5 inch tire) decreased EGT's and improved torque. The biggest thing that will improve EGT's is timing, I'm currently running 24.5 degrees of timing at 2k RPMs which now burns most of the fuel in the cylinder making more power to the wheels and little expanding gases to the turbo hence why my boost is near zero empty. Now towing once my engine load rises above 20% then my timing retards to about 15 to 17 degrees and now I making boost and more power because the timing is retarded so more expanding gases are sent to the turbo. The other thing is my engine oil temperature is 30*F cooler than coolant temperatures so if my coolant is 195*F my oil temp floats 165*F so little heat energy is being wasted on my oil from excessive flame exposure to the piston top and cylinder walls. 

 

(Summer of 2023 Parma ID)

 

Now Thor (2006 Dodge 3500) in the picture above was one of the worst towing vehicles I own. EGT's are through the roof with a HE351 turbo which is (60/60/9) then the factory tune is heavily retarded and made for a poor towing of my RV to get to Parma ID. Coolant temperatures rise sharply climbing, EGT's are high even on flat ground towing at 55 to 65 MPH. Beast on the other hand just set the cruise and go towing the same 8,000 pound RV. Thor has +50 HP DAP injectors, no tuner, 3.73 gear ratio on 265/70 R17 tires. The final ratio of 3.73 as well. 6-speed transmission which does not help at all being the top two gears is the very same as a 5-speed. The best I can tow over a 7% grade with my RV is roughly 30 to 35 MPH with the EGT's banging at 1,200 to 1,400*F. Would a tuner help this absolutely. This is a 325 HP Common Rail Cummins being out done by a 2nd Gen at this point that is 500 HP.

 

I feel that people are needlessly adding bigger turbos and then finding out that the spool point is higher in the RPM span and not getting the launch abilities. I've seen several people with improper setups and end up struggling to gain back the efficiency of the engine because of excessively large turbos, oversized tires that degrade the final ratio, then EGT's are excessively high. Even my other turbo the HX35/40 hybrid spooled later being it was only a (60/60/12). Boost was even lower at cruise state which with my tune typically sat like 0 to 2 PSI at 65 MPH.

 

(Fall of 2023 Florence ID at 6,500 feet)

 

Another example I've been doing is firewood runs up to 6,500 feet elevation on the west side of Florence ID. Climbing 9% to 10% grades. Even in high altitude still zero issues with EGT's because of the final ratio being 3.69 from the 245/75 R16 tires. Even loaded with 2 cords of lodge pole trees cut into 12-foot poles. No issues for back-country travels. Just for info my tallest local peak (Heavens Gate) is right near 9,000 feet you can drive to from Riggins ID.

 

Economy wise I just made a trip to Lewiston for food. I filled up in Lewiston ID which is roughly 125 miles from me and barely burned a 1/8 tank to get back home 2.5 hours away. Still keeping good MPGs. 

 

• Quadzilla Adrenline Tuner (Custom tune)
• HX35W stock turbo (54/60/12)
• +150 HP DAP VCO Injectors (7 x 0.010) custom popped to 320 bar
• 4 inch exhaust
• BHAF (no cold air intake)
• 245/75 R16 tires
• NV4500 transmission with Valair Dual Disc Clutch
• AirDog 165
• 55 MPH - boost 0 PSI and EGT's 450 to 500*F
• 65 MPH - boost is 2 to 3 PSI EGT's 550 to 600*F