3-Pc. Dyna-Flex 8" Chrome Exhaust Pipes Install

INSTALLATION OF 3-PIECE DYNA-FLEX 8” CHROME EXHAUST PIPES

ON 379 UNI-BUILT PETE WITH ROD PICKETT LOWER ELBOWS AND CUSTOM-BUILT 8” STAINLESS ‘TEE’ PIPE.

Parts cost approximately $2,850. This includes:

• Two 8” x 114 turnouts with pickett elbows
  
• Four 8” “wide” style Pete cab clamps
  
• Two chrome lower cab exhaust mounting brackets
  
• Eight rubber exhaust mounting grommets
  
• One 4 State special built 8” outlet and 5” inlet stainless exhaust tee
  
• Four 8” band clips
  
• Two 10” long pieces of 8” flex pipe
  
• One 5” band clamp
  
• Two 8” chrome support clamps to hold tee pipe to chassis

All parts available at www.4statetrucks.com

Typical installation time is 6 – 7 hours.

STEP 1:

• Completely remove original exhaust system, including mufflers, stacks, elbow, flex pipe and exhaust “tee” pipe.
  
• It will also be necessary to remove the 5” diameter exhaust support clamp from the chassis and replace the lower portion of the clamp/strap assembly after step number 7.

STEP 2:

• Remove the original lower cab exhaust brackets.
  
• Install the chrome replacement brackets and new rubber mounting grommets .
  

  

  
  

  STEP 3:
  
  If your upper cab exhaust bracket has a large “C” shaped muffler support bracket then you need to follow these steps:

  
  
• Grind thru the rivets that attach it to the cab bracket
  
• Discard the “C” shaped bracket
  
• Cover the cab and glass areas on the cab during the grinding procedure so sparks do not get imbedded in the paint or glass.
  
• CAUTION – Wear eye protection when using grinder and cut-off tools!
  
• Install new rubber exhaust grommets directly into cab bracket.
  

  

  
  

  STEP 4:

  
  
• Install custom tee pipe and loosely connect 5” connection.
  
• Support tee pipe with wood blocks or jack stands temporarily.
  

  

  
  

  STEP 5:
  
  

  
  
• See photo – the inlet end of the DYNA-FLEX elbow is reduced to 5” and intended to be used with 5” diameter tee pipe. We have chosen to remove the “reduced diameter” portion of the elbow using a die grinder and cutoff wheel. This should help with eliminating “back pressure”.
  
• CAUTION – Wear eye protection when using grinder and cut off tools!
  

  

  
  

  STEP 6:
  
  We find the easiest method to install the three-piece type exhaust pipes is to fully insert the elbow into the spool assembly and then install the elbow and spool on the truck as one assembly. DYNA-FLEX supplies hi-temp silicone with all three- piece pipes. This will further eliminate potential exhaust leaks. We advise that you use the silicone on both spool connections.

  
  

  

  
  

  

  
  

  STEP 7:

  
  
• Lift the spool and elbow assembly into position.
  
• Attach the tee pipe with the short piece of the 8” flex pipe. This operation will require two people to minimize unnecessary scratching and blemishes.
  
• Slightly spread open the lower 8” chrome mounting clamp and slide over the top end of the spool and slide it down the spool into correct position.
  
• You can put a rag or masking tape around inside area of the chrome 8” clamp as you slide it down the spool to eliminate possible scratches to chrome exhaust.
  
• Slide the upper 8” mounting clamp over the top end of the spool and loosely install all four bolts in cab brackets.
  
• Check alignment on elbows, spools and tee pipe.
  
• Tighten all connections.
  

  

  
  

  STEP 8:

  
  
• Slide the upper stack section on to the spool section. Don’t forget to use silicone once you get the turnout positioned at the “angle” you like best.
  
• Tighten clamp completely.
  

  
  

  STEP 9:

  
  
• Do a visual inspection beginning at the “tee” pipe inlet and work your way up to the upper cab clamps.
  
• Check each clamp connection.
  
• Make sure all are bolts and clamps are tight and secure.
  
• Start vehicle and check for exhaust leaks.
  

  

  
  

  

  
  

  STEP 10:
  
  
  
  Job done! Thanks goes to Dan Thompson for letting us photo his 99 Peterbilt “Independence” for this Special Installation How-To Feature.

  
  

  Note: If you remove the two original mufflers, D.O.T. will require you to install a muffler under the vehicle (Federal Law).