I just replaced my entire exhaust system, turbo back on my 95 GMC (close to Chevy content) 3/4 ton with a straight pipe system, 3 inch leaving turbo, 3.5 inch at bottom of down tube, 4 inch from muffler area back. No cat, no turbo. It runs like a scalded gazelle now. Deep low rumble, not objectionable at all but definitely not stock. I love it but I just realized that I am going to be spending 5 months on the left coast. The sound and the presence of a 4 inch exhaust behind the passenger tire are a dead give away to anyone with two or more gray cells and a little bit of auto savy. One look under and that monster pipe and no cat or muffler jump out at you. Does anyone have any sage advice on what to expect from the CHP concerning a radically modified exhaust on a vehicle licensed out of state (non Calif)?
Is it A Hd. emissions 8600 GVWR truck If your 3/4 ton K-20 is 6000 GVWR you will need A cat and all that HP robbing stuff I know that my 1981 k-20 didn't have cats with Hd. emissions 8600 Gvwr all it has was the AIR injection system but it fell off just before the heeder were installed! If you don't need A cat just get A Flowmaster muffler you can't beat the flowmaster for performance and sound
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California law requires that all vehicles must be equipped with an adequate muffler to prevent excessive noise from the exhaust system. It also prohibits the operation of a passenger vehicle (other than a motorcycle), or a truck with a Gross Vehicle Weight Rating (GVWR) of less than 6,000 pounds, that has an exhaust noise level greater than 95 decibels, when tested under specified conditions. If you have been issued a citation for operating a vehicle in violation of Vehicle Code Section 27150 or 27151, you must take your vehicle to a state Referee Center.
Note: The Referee is only authorized to inspect and certify passenger cars and trucks under 6,000 GVWR that have been cited for a violation of Section 27150 or 27151 of the Vehicle Code. The maximum decibel level applies only to those vehicles. Citations issued to other vehicles (motorcycles, trucks exceeding 5999 pounds GVWR) are not part of this program. Check with the agency that issued the citation, and/or the court, to find out how to show proof of correction for these other vehicles.
The following steps outline the procedures you'll need to follow to get a certificate of compliance, which shows your vehicle's exhaust noise level is within the applicable standards.
STEP 1
If you feel your vehicle's exhaust system has been modified or has deteriorated so that the noise level exceeds current standards, you should have the exhaust system repaired before proceeding to step 2.
OR
If you have reason to believe that your vehicle's exhaust noise level meets the current standards, proceed directly to step 2.
[Note that citations have a court appearance date.] [Timely action can help you avoid additional fines and penalties.]
STEP 2
Have your vehicle tested at a state Referee Center. To make an appointment, call the Referee Scheduling Center at (800) 622-7733. Have the citation and vehicle registration with you when you call. The Center will tell you any fees that will need to be paid for the test.
STEP 3
The Referee will conduct an exhaust noise level test in accordance with the Society of Automotive Engineers (SAE) standard J1169, May 1998, to determine if your vehicle's exhaust noise level exceeds the noise standard (95db).
If your vehicle meets the standard, the Referee will give you a "Certificate of Compliance." Take the certificate to the court (See Step 5).
If your vehicle does not meet the standard, the Referee will give you a report that lists the recorded decibel readings. Your vehicle must be repaired to meet the standard of not more than 95 decibels (See Step 4).
STEP 4
If your vehicle does not meet the standard, additional repairs must be made before you can make a second appointment with the Referee Scheduling Center.
STEP 5
Once your vehicle receives a "Certificate of Compliance" from a Referee Center, present the certificate to the court as proof that your vehicle is in compliance with California law.
NOTE: Inspection fees and any necessary repairs are your responsibility. You may also be required to pay a fine and other legal costs when reporting to the court. Also, note that most citations have a deadline. Timely repairs can help you avoid additional fines and penalties.
If you have any questions, please contact the local law enforcement agency that issued the citation or the Bureau of Automotive Repair at (800)
Yes it is a 8600 GVWR truck. No EGR, an "F" engine.
...snip....
... does this apply to out of state vehicles, ie non resident, a visitor?
...snip.... (probably a lot of pertinent stuff though)...
I was thinking about welding a cat shell on (gotta find one that is over 3.5 inches thick) so that it would at least appear to be present. I could do the same for the muffler? From what you said, if I keep my foot out of it (which I do anyway) and it really isn't noisy anyway, no crackle, no roar, mostly a deep throbbing sound I may not upset anyone. The truck will be parked most of the time I am there (schooling) and when I drive it I will behave myself.
Boy, I do dislike bureaucracy. I don't want to upset anyone but I am not readily going to give up the power and economy I have just worked so hard to gain.
Fortunately it doesn't smoke, no blue for burning oil (which it doesn't do) and no black for excessive rich diesel. A little white on start up occasionally, that is all.
Thanks for the input! At the least I am now better informed. That is what I needed, not necessarily what I wanted.
I don't see how a state can FORCE you to comply with their emissions regulations when you are only visiting. Same would go for the noise, if you state allows your vehicle as it is, why should you change your exhaust because the CHP doesn't like it while you're visiting the state?
How long you going to be in California ? If your here for, (I think) It's
60 days then you will have to get it a smog check and California tags. The smog station will check it, and you wont pass. Then its going to be time to pay the piper to get it legal.
For the same reason they used to write tickets for Arizona vehicles with window tint that met Arizona standards but exceeded California standards?? Do they still do that?
Contrary to popular belief CATS restrict very little power these days and it is more a state on mind than a reality on what is gained without them. I hope one day they tighten the laws more on cutting them off because we all breath the same air.
If it were a gas engine I would be in total agreement with you, but this is a diesel. The cat on a diesel is primarily a soot collector. I would put my diesel up against any cat equipped similar engine and would win (would have a cleaner exhaust/less solid particulate).
actually when you goto another state on short term for work or school or due to family emergency the state goes by your legal residency which means they can't force you to do anything that concerns their emissions laws thats why lets say my legal residency in say nevada and I goto california to work everyday and shop and do everything else ,the cops(they don't have nothing to do with emissions)they can't make you get any testing done in the state of Ca. because that vehicle legal state of residency is in nevada ,but now comes to the flip side is they can get a vehicle for being excessively loud because it ones fall under the same laws as disturbing the peace and they can get you for safety violations like bald tires leaking brakes ,leaking exhaust ,leaking gas ,you get the picture that is a safety hazard for not just you but for anyone else to travel safely down the road ,now if the exhaust is a factory approved system and is not modified by the owner then the cops can't do too much there either because it falls outside of their jurisdiction because it is legal in his state ,why because a loud exhaust is not a safety concern thats why motorcyclist have to wear a helmet in some states and not others and why for years seatbelts were not enforced in some states but could get fined in others there are some shades of grey in state laws everywhere but it comes down to this if your not a legal resident of a state then you are not under jurisdiction of the states DOT requirements usually but law enforcement requirements you are, you just have to research it and see what is required of out of state vehicles . This is why someone from Jersey can take his hotrod to a show in PA ,without fenders and not get fined
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