6.7 short comings that need to be dealt with

[DonFitzwater]

As a newer owner of a 6. 7 with automatic trans, I'm simply looking for an idea of what usually goes wrong with these trucks. I've done a bit of searching and have found what appear to be the random type failures but haven't really been able to establish what is going to fail like the older trucks(trannys, injectors, hvac doors etc).

I plan on keeping this rig for a while and will be keeping it stock for the foreseeable future. The only mod I plan on doing is a torque converter at some point.

Just looking for ideas on what to look for.

 

[cerberusiam]

If you are still using the factory filtration, more is better. Both solids and water separation will enhance the life expectancy of injectors and the rest of the fuel system.

The one issue with the engine is the EGR and VGT turbo must function correctly together or the chances of blowing head a head gasket sky rockets. As long as you keep it stock and maintain the emissions systems it is pretty good, remove the EGR, turn up the power, keep the stock trubo and it is only a matter of time until problems surface.

The 68RFE has a few weak points that you need to be aware of. The low\reverse clutch and roller sprag are not the strongest. Burnouts and\or massive TQ loading\unloading with heavy throttle in low or reverse will eventually cause issues. Use it like it is meant in close to stock mode and moderate the right foot operation will result in less problems.

 

[Cummins12V98]

Nearing 36K and no problems.

 

[DonFitzwater]

Cerb, any issues with removal of the EGR and keeping it stock? Other than a CEL that is.

 

[cerberusiam]

Removing and\or blocking off the EGR is where the potential porblems start. There is some pretty good evidence the EGR systems acts as an accumulator for exhaust back pressure created by the VGT turbo when it does its thing opening and closing. Removing EGR and adding power is almost a sure fire recipe for HG problems, kinda lack tapping the wire on a VP44. A lot has to do with driving style and use of course but the potential ends up being there.

It is not the back pressure that is the issue rather it is forcing more exhaust back into the cylinder that is creating some detrimnetal cylinder conditions. The design of the block and the head has some issue that show under certain conditions like that. In addtion to the loosing the EGR it looks to be benficial to remove the VGT turbo and go with a standard one to alleviate the issue. Stock is not as big an issue but there are cases where the HG's gave up under stock fueling when extensive mods to the emissions systems were made.

Anything that disturbs the operation of the engine from as-delivered form can have repercussions. Definitely not the same as the 5. 9 in that respect.

 

[DonFitzwater]

Sounds like she'll be staying stock in this case. However, if you delete the EGR and VGT, are you also eliminating the exhaust brake?

 

[cerberusiam]

Sounds like she'll be staying stock in this case. However, if you delete the EGR and VGT, are you also eliminating the exhaust brake?

Yep, you loose the VGT brake and would have to make other arrangements plus fool that system or it would likely go into limp mode.

 

[DonFitzwater]

Stock it is! I'm not giving up the brake.

 

[RVTRKN]

Keeping them stock is the best way to go with these EPA burdened engines, but the easiest thing you can do to help in the longevity of the 6. 7, is to get into the habit of turning the EB on every time you start your engine, it helps in keeping the VVT from sooting up.



BTW, be careful when they want to reflash your ECM with updates, it certainly has caused me headaches with my C&C.

 

[DonFitzwater]

My dealership tried to talk me into deleting everything and installing an H&S performance tune... ... ... ... ... the head gasket issue was my main concern. Now, according to my dealer, the current software vs on my truck will initiate a no start condition if I install a non Chrysler program. How much of their claim is accurate?

 

[RustyJC]

I've been through the "bombing" phase with my 2002 ETH/DEE 3500, thanks. This one is stock, will stay that way and even has an extended warranty. If it breaks, the nearest dealer can fix it.



The only problem so far happened this month - an output speed sensor on the 68RFE went bad and threw it into a CEL/no-shift/limp mode condition. I could force manual shifts with the +/- switch to get it to the dealer where the problem was taken care of.



Rusty

 

[Texas Ted]

Bone stock, no problems, 60k miles
Ted

 

[cerberusiam]

Now, according to my dealer, the current software vs on my truck will initiate a no start condition if I install a non Chrysler program. How much of their claim is accurate?

They did start adding encryption or a checksum or flag or something to stop tuning, not sure when. The tuner has to be able to handle that or you will get the hook.

 

[TulsaOkie]

Zero problems at 131,000 on a 2011, has never seen a shop to be repaired just maintence. 2007. 5 lost the transmission at 335k, truck has 387,334 and keeps on ticking... .

 

[RVTRKN]

Trouble free until Dodge reflashed it, I hate the new program when in regen, but mine has the standard transmission.

 

[DonFitzwater]

What's it doing? My auto is nearly seamless when a regen happens.

 

[pcarlson]

Stock and 50,000 miles. Just maintenance and no troubles.

 

[JCJohnson]

I've got 73,000 and it's time to replace a front axle U-joint and the hub on the other side. I still love the truck, but not that this happens this soon!

 

[rscurtis]

If you plan to keep the truck, install a free-spin kit and U-joints with grease fittings.

 

[DonFitzwater]

If you plan to keep the truck, install a free-spin kit and U-joints with grease fittings.

That'll be the first thing after the warranty is gone. And a trans overhaul with a sun coast converter (unless Goerend makes 68rfe parts by then?)