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Diesel conversion Legalities?

21K views 18 replies 12 participants last post by  cetane 
#1 ·
Anybody here have any problems in NY registering a gas truck that was converted to diesel? Are there steps that I need to take beforehand? Things I need to get together? Any advice?:confused:
 
#3 ·
There is also the mostly unenforced Federal law, which would pretty much eliminate swapping these motors into most, if not all, highway vehicles. The 3.9 was never EPA approved for use in light duty vehicles. It also doesn't meet the requirements of being either a "replacement" or "upgrade" engine. Replacement being an engine exactly like what was removed- removing a 5.2 from a Dodge Ram and installing another 5.2 is a replacement. Removing a 5.2 and replacing it with a similar setup 5.9 (which was optional for that vehicle) is an upgrade and is also allowed.

Then there is an approved "swap". This means removing the original engine and replacing it with something completely different, but you must keep the emissions equipment from whichever is newer, the vehicle or the engine. You can put a 2000 Chevy V-8 into a 1974 Vega, but you would have to use the 2000 emissions equipment. If you put a 1975 350 into a '95 Camaro, you need to fit the Camaro's emissions equipment to the old 350.

You also can't install a diesel into anything that didn't originally have a diesel. You could put a 2000 Dodge 5.9 into a 1985 Chevy diesel pickup, but not into a Ford Expedition because it never came with a diesel.

Those laws are pretty much unenforced though, except in California. You pretty much have to worry about local and state laws. Here in NH we have a basic emissions inspection that just consists of plugging the inspection computer into the OBD-II diagnostic port to make sure there are no current codes. They only do this with 1996+ vehicles, 8500 lbs. GVW or less, and depending on year, some originally equipped diesels are exempt. Now that I can no longer do my own inspections (there are ways to fool the state computer) my 2000 4bt Durango will no longer pass.

Just pointing out the fed. laws for those who don't know and may care. Most don't care.

Jim
 
#5 ·
I would call until you find someone who can answer.. What nhdiesel said pretty much seems about right in my experience... Here in Utah it is almost a non issue and I recall from my 1990s and earlier when I lived in NY state that it was all pretty easy and basic and never had any emissions checks where I lived, if it helps...
 
#6 ·
In my experience, if you live where there are NO emissions checks, or where the emissions checks do NOT include a visual scan of components (sniffer only), then the rules are just:

1) Same year or newer engine
2) All emissions equipment for engine going in must be maintained.

If you have emissions checks, especially with a visual scan, then it can get real complicated real quick.
 
#7 ·
Some states have a rolling 25-30 year exemption on emissions too. In Cal when I swapped a chevy V8 into my 72 Z, it technically wasn't legal, but it wasn't smog tested so you could get away with it. I did ALMOST get busted once though on that, its very infrequent, but at the time they were running roadside test as sort of a survey (so they said), this was in about 99 or 2000. My wife called me and told me about it, it was near our house and had I get stuck in it, it would have probably have been problems. While the car was exempt, it still didn't mean I was not SUPPOSED to have the emissions hooked up. Needless to say in that hot rod it had nothing but a crankcase vent to the air cleaner. As I say thats very rare and in some states counties that don't have testing are probably never going to check it. That was in Cal. btw, but in your case as mentioned above, I sure would get more info before I put something in that got you in trouble.

Regards,

D.
 
#8 ·
If you read the fine print of the EPA regulation it states specifically you must have all emissions devices in place that were originally EPA tested and approved for for that vehicle type & chassis that was a mass produced vehicle sold here in the USA. This would mean that it is illegal to transplant a 1982 6.2L GM diesel from a 1 ton chassis into a 1982 1/2 ton chassis because the 1 ton did not have the EGR valve. This would be normally be checked doing the visual inspection required in some states such as PA. According to the now retired head of our state inspections, if you install a 2010 engine into a 1985 chassis the engine must meet all of the unimproved emissions requirements of the vehicle as built and approved in 1985, not the 2010 specifications of the engine. I had a few conversations with that fellow and he was quite willing to teach anybody who wanted to learn.
 

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#10 ·
Bob is right. My diesel conversion is 100% illegal. That is, if the EPA shows up and inspects my truck. However, when I got my emissions testing paper in the mail from the state of Illinois I managed to talk my way into getting it diesel exempt from testing. This is pure luck though, and even in the eyes of Illinois inspectors who REALLY know their vehicles, my truck is illegal. I only got away with it because it was a Dodge Ram and all 2nd Gen Rams look the same regardless of weight class. I'm using a 93' EPA certified engine in an 01'. Not legal....

PS I hope the EPA or Illinois DMV doesn't read this....
 
#11 · (Edited)
After reading these posts, I'm realizing that my rig might not be as legal as was once thought. It was badly asumed that as long as the engine was newer than the vehicle, then the sky was the limit as to what could be dropped into the engine compartment. While we don't have any smog testing in western Wisconsin, I should still be vigilant for roadside test points during my travels in other areas as well as keep my nose clean with the State Patrol. There's no reason to draw any more attention than what is absolutely necessary.

Thanks for clarifying this isue,

Brian

P.S. So would it be somewhat environmentally friendly to route the crankcase vent tube back up to my air cleaner inlet?
 
#12 ·
The good thing about the Federal requirements is that the official federal position is to leave enforcement up to the states as they see fit. It seems kind of needless to have strist federal laws if they aren't going to be enforced. Just leave it up to the states to decide. But officially, as long as you are legal for your state's laws, you won't (at this time anyway) have to fear any problems with the feds.

Jim
 
#14 ·
If you regester it as 8600 GVW the emissions portion of the inspection is visual only (no plug in and check for codes) I've never seen or known of any one actually doing a visual check of emissions equipment. They all check the normal stuff (lights, brakes, E brake, ball joints, tie rods etc)
 
#15 ·
Just finished a 6BT swap into a 91 suburban. I am in CA. in what they call an "enhanced smog area". After 2 trips to the state referee, and a physical trip to the local DMV, I am offically a diesel vehicle, exempt from smog checks. Just got my vehicle tags yesterday. I was told that the vehicle must be at least 8600GVW or greater, because the original vehicle was rated at that (1993 dodge). All the original sensors and associated wiring, and computer must be installed. They even wanted the original contactors(relays) for the heating grid. The engine must also be the same or newer model year of the vehicle recieving the engine. I realize that I am in CA. not NY, but we have stupid smog laws, we even have a self appointed organization that creates laws, and is self funded by writing ticket!! They are called the "Air pollution control district". I read the laws, and made phone calls, before the swap. You must find the loop hole in the law. After all this, the state referee was impressed with the swap, and asked alot of questions about it. In the near future, according to the referee, the laws will be changing, so get the projects done and through the system quick.
 
#17 ·
Does anyone actually have or has seen info on where it is it 'illegal' according to the EPA? I realize there is the vehicle size category issue (so your truck should be heavy if using a 4BT) but I feel this is a pretty minor technicality and if your state is OK with it then I feel that is fine. The EPA will never, ever enforce this.
 
#18 ·
ALL Dodge Diesel optioned trucks were rated at 8510 GVW and above. This was part of the emissions requirements back in 1988 and why Dodge never installed a Cummins in a half ton or a heavy half ton/light 3/4 ton (5001-7500# class) pick up truck. At that same time gasoline engine trucks with a GVW of less than 8500 pounds were required to be equipped with similar emission equipment required on all passenger cars of that era. There has always been a set of emission requirements on all passenger cars and light trucks since the dawn of air injection reactor pumps and catalytic converters were installed. Also, bordering on politics which we won't go into, I would say "Never say never" with the current political group that we currently have in charge of things. To them anything other than a hybrid or battery powered vehicle is strictly a dinosaur that need replaced. The original EPA rules are attached to a prior post in this thread and are linked in the Tech Index.
 
#19 ·
I was at the DMV the other day taking care of some things, and I asked one of the people who work there this question. They didn't know offhand but asked their manager. The answer came back that there should be no problem whatsoever at the DMV, just show the reciepts from a shop showing the work done. It would have to be inspected though afterwards by a diesel shop when the reggie was up again. Sounding good.
 
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