F-150 Exhaust

[cavasinj]

Hey all - I know it's not an issue specific to a 1991 F150, but... I recently purchased this truck as a farm truck - approximately 100,000 miles, 5.0L, 4x4, manual. I knew it had been converted to having two glasspacks or cherry bombs, and didn't care as I wasn't using it much. However, now that I am using it more often, I am finding these to be deafening. They are mounted directly underneath the cab, and have no tailpipes extending out the rear. My question is: can adding the extension off the outlet of these divert the sound, and make it less deafening in the cab, or should I scrap them completely and just get a new muffler installed as it would have originally been?

Thanks in advance,
Joe

[Torch]

I used to have a 77 F-250 with 2.5 inch dual exhaust with four foot long glass packs then eventually exited out the sides of the truck behind the rear wheels, the truck was literally in the exhaust shop ALL DAY LONG but by the time it was done the truck had a very quiet mellow sound to it with a nice rasp when you floored it.

But as the years went by and the glass packs wore out it became rather loud, that is just the way glass packs are.

Well, to answer your question, the longer you make the pipes the deeper of tone they will resonate at, the lower the pitch you can get them the less annoying they will be, and the further away you can get the exhaust gases from you the better off you will be.

[LoseDevil]

Sounds like your problem is a combination of glass packs and dumps. The dumps would be if the exhaust is angled at the ground directly under you cab and this can be deafening. In this case extending the exhaust pipe to the rear of the truck will help.

However, if it's the cracking glass pack, then perhaps you should consider cutting them out and installing straight exhaust (loud) or installing something more mellow like a flow master muffler.