How long is too long to let the truck sit?

[Will_T]

Someone just started another thread asking how long a hemi can sit without being driven. I realized I think about this with my truck also. I have a older Subaru that is my daily driver so between camping trips the truck does not get much use, only once in a while pulling my utility trailer, or needing to move something using the bed. I took it out on a drive last week for no reason other than it had been sitting for about 3 weeks, only having been started a couple of times when it needed to be moved at home. It will never sit unused for several months or longer but I can see it not being used long distance or towing for a month or two sometimes unless I purposely take it out just to run it. I think about the DEF and the fuel mostly with a 52 gallon fuel tank and DEF having an expiration. What is the point at which you would start to be concerned?

 

[jkempken]

As long as you are using fresh DEF and the tank is between 1/4 and 3/4 full you should be good for a year. Do not want to have it sit with a full DEF tank in the dead of winter as it can crack the tank when it freezes. For fuel it should be the same, if worried about it going bad just put in some Hotshots EDT and all should be well. A lot of us guys with 19's and 20's put it in every fill up anyways as cheap insurance for the CP4.

 

[Will_T]

As long as you are using fresh DEF and the tank is between 1/4 and 3/4 full you should be good for a year. For fuel it should be the same, if worried about it going bad just put in some Hotshots EDT and all should be well.

Thanks. A year, not what I expected! I should have no problems then. I thought I had read that DEF is only good for 5 or 6 months if temps spend any time above 90 degrees. So that was my main concern as a tank of my DEF could easily go 3 or 4 months before getting to the 1/2 way point where I add a fresh box. I have been using Hot Shots EDT so I will continue with that. I am still on my first bottle at 3,000+ miles so yes it is inexpensive to use.

 

[John Jensen]

Your described downtime is no problem, with today's diesel fuel and using EDT you will be fine.
If you ever have long term downtime, use PRI-D. It is without a doubt the best for diesel storage.

 

[Will_T]

Your described downtime is no problem, with today's diesel fuel and using EDT you will be fine.
If you ever have long term downtime, use PRI-D. It is without a doubt the best for diesel storage.

Thanks - I was most concerned about the DEF. I wondered if some of these DEF system problems we read about might be caused by DEF in the tank getting several months old, especially in hot weather.

Also wondered if adding fresh DEF to old makes the full tank better or if the old DEF just adversely impacts the newly added DEF. I guess I started thinking about this when I read how short DEF life is above 90 degrees and realizing this year almost all our days have been over 90 with many over 100. A few over 110. But I guess if it really was an issue, diesel trucks in Phoenix would all be in trouble.

 

[John Jensen]

Thanks - I was most concerned about the DEF. I wondered if some of these DEF system problems we read about might be caused by DEF in the tank getting several months old, especially in hot weather.

Also wondered if adding fresh DEF to old makes the full tank better or if the old DEF just adversely impacts the newly added DEF. I guess I started thinking about this when I read how short DEF life is above 90 degrees and realizing this year almost all our days have been over 90 with many over 100. A few over 110. But I guess if it really was an issue, diesel trucks in Phoenix would all be in trouble.

I agree, I've had those same concerns. I am a low miler, only use my 2020 3500 HO for towing my travel trailer. The rest of the time it sits, up to 4 months. I also use EDP.

From all my reads there doesn't's seem to be a big DEF related problem. I've read where some get codes of bad DEF. DEF has to be at 33%. Our trucks alarm at 22%.. I also read where it causes crystallization at the injector. And that is supposedly easy to clean. Because of what I have read, when I can, I dilute my DEF to 1 gal distilled water to 2.5 gals DEF (24%). Why? It may reduce crystallization problems.

You mentioned: "Also wondered if adding fresh DEF to old makes the full tank better or if the old DEF just adversely impacts the newly added DEF." The new and the old obviously mix. If the percent DEF is above 22 all is okay. If not, it requires draining the DEF and adding new. I've had to do that on my 2016 1500 Ecodiesel, not fun but easily doable.

 

[Will_T]

If the percent DEF is above 22 all is okay. If not, it requires draining the DEF and adding new. I've had to do that on my 2016 1500 Ecodiesel, not fun but easily doable.

I have not looked, but there is probably no drain plug in the bottom of the tank? I suppose that would make too much sense.

 

[John Jensen]

I have not looked, but there is probably no drain plug in the bottom of the tank? I suppose that would make too much sense.

Correct, no drain plug. But here is a hose that tiu can release with your fingers , put in a pump tube and drain it. Lots of video on google

 

[Nick]

Blue DEF has come out with another type of DEF that is supposed to mitigate some DEF related problems . I am not sure what is in their magical blend but it is about $8 more than their regular DEF .

 

[H3LZSN1P3R]

Dont let it sit for that long any more than a couple weeks when seals dont have oil they can start to break down and dry up then leaks start to develop

drive it once a week even just to go to the store quick anything to get oil moving and keep the brake rotors from rusting and what not….

DEF just put small amounts in

 

[Will_T]

Blue DEF has come out with another type of DEF that is supposed to mitigate some DEF related problems . I am not sure what is in their magical blend but it is about $8 more than their regular DEF .

I have seen this and wondered if there really is any advantage to it in spite of their marketing.

 

[Will_T]

DEF just put small amounts in

At first I thought huh?... but it does make sense as long as it is OK to store a partial box. It would certainly be better for it to expire in the box rather than in the tank. And in hot weather the partial box could be stored in a much cooler place than in the truck's DEF tank. Right now I have about a 60% full DEF tank and it was last filled about 7 weeks ago.

 

[H3LZSN1P3R]

At first I thought huh?... but it does make sense as long as it is OK to store a partial box. It would certainly be better for it to expire in the box rather than in the tank. And in hot weather the partial box could be stored in a much cooler place than in the truck's DEF tank. Right now I have about a 60% full DEF tank and it was last filled about 7 weeks ago.

Idk about where you are but you can buy 1 gal jugs here aswell as 2.5 gal perfect for these situations

 

[Will_T]

Idk about where you are but you can buy 1 gal jugs here aswell as 2.5 gal perfect for these situations

The couple of times I needed DEF, the shelves were almost bare. Last time, I got the last box at a Walmart and the date code said it had been manufactured about 10 days previous. Was told there is a shortage of it. Like most everything else I guess. Not sure now as it has been almost 2 months since I needed to buy any.

 

[H3LZSN1P3R]

The couple of times I needed DEF, the shelves were almost bare. Last time, I got the last box at a Walmart and the date code said it had been manufactured about 10 days previous. Was told there is a shortage of it. Like most everything else I guess. Not sure now as it has been almost 2 months since I needed to buy any.

Odd i have never seen a shortage here