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:
All parts available at www.4statetrucks.com
Typical installation time is 6 – 7 hours.
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.
Install custom tee pipe and loosely connect 5” connection.
Support tee pipe with wood blocks or jack stands temporarily.
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!
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.
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.
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.
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.
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).