Just got a Fleetguard muffler 86131m, apparently much like the Nelson ? But there is no In or Out indication. One end is cupped or conned out and the other end is cupped or conned into itself. There does seem to be a little difference inside as well. Any tips sure would be appreciated. Really don't want to do this twice.

 

I think the cone out end is the exit end. My Donaldson has the arrow pointing to the cone out end as the exit side. Is the Fleetguard baffled inside?

 

Dumpster, i installed mine cone pointing downstream.

 

The domed end is the outlet end. Supply your email and I can get a drawing for you.

 

Actually, you can get a drawing by going to www.cumminsfiltration.com and leaving a message. They will send you a drawing.

 

If the muffler is in an upright position, like on a semi truck, it is in the direction that the rain water will not be trapped on the top.

 

Thanks for all the replies. It makes sense that the cone end be the exit in the event that it is mounted Verticaly on a truck. No there are no baffels inside. You can look straight through. There is an area in the center for about 10" that doesn't have anything, the rest has a pipe that is filled with about 1/8" holes for the baffeling effect. Hope its not to loud.
I ordered a Nelson but the Fleetguard was what showed up. Thanks again for the info.....

 

The domed or cone end flange is the outlet side. The cone is needed and used for water run-off if mounted vertically. The Fleetguard brand name has replaced Nelson in the aftermarket for exhaust products. I'll take away from the comments that Fleetguard aftermarket exhaust mufflers need better identification on the part for inlet vs outlet ends. Thank you for purchasing a Fleetguard exhaust product!