Hi all, wanted to your opinion/ advise on eliminating/avoiding a cabin drone on by ‘92 truck, I went over the search engine but could find anything close to my situation, apologies if I’m covering something long discussed and solved but most of what I could find was related to non-stock engine and exhaust systems.

Here it goes: I just got a ‘92 F250 CC / 460 / ZF5 / 3:55, all stock including what I believe is the exhaust pipes (according to the original owner). This is my second 460 and the first one was a '91 SC / E4OD and my reference point is experiencing no drone with that truck either with original exhaust (of course) or aftermarket Flowmaster 40. it was quite pleasant listening the rumble and tune going over the gears but once on the highway on OD it sounded quite like the stock set up and no drone at all in the cabin. Now with the OBS there is cabin drone right past 90km/h 'til about 110km/h where it attenuates a bit but not much. I did not notice any exhaust leaks. Perhaps I should question: are these actually stock? My '91 had two in and two out from the muffler, and straight pipes, were curved 3" out stock? I have plans on putting a Super 44 but I'm not sure if the drone will go away or worsen, or if the problem lays somewhere else… Anyways here follows a few pictures for identification (please don't mind the ancient tire...I'm getting those changed haha). Thank you all, and long live the big block!

 

Definitely doesn't look stock. Just replaced on my 94 and it is 1 in 2 out. I took it off complete for the Banks set up. No drone at all.

 

 

so no something is not stock

 

I suspect the stock cat is gone or has been gutted, they were quite effective noise supressors. Whatever you do try not to put a DroneMaster noise amplifier on the truck... unless you want to completely drown out the radio, get a Dynomax super turbo or a Magnaflow.. somthing that has actual sound absorbing material inside. You mght also consider putting an aftermarket cat on it to take the edge off.

 

idk how much it works for a v8 with a muffler, but a glasspack would, under a lot of v6 car applications, work for a new resonator,however they are limited in life span but they can be easy replacement when placed in a good straight shot and also clammped with those band clamp things and maybe some fiberglass tape

 

4cyl automotive engines are also notorious for generating cabin drone so every time I have done exhaust work on one of those it usually involves installing a resonator(glasspack) somewhere ahead of the muffler. And yes that makes the exhaust almost dead silent in the cab.

 

I wonder if it would do much for a v8 then, considering its not quite the imbalances of v6 and i4 but hard to say i guess.
this was a 77 LTD with a 400. the cat was there, the muffler was too(original) but it had a single hole it in which looked like a puncture but I never did anything about it. had a slight drone but I attributed that to the muffler under the trunk area not being as ford intended (hole was not factory I presume)
at cold start it was kinda cool