CUMMINS NW Cummins 1551258 Onan Muffler

The Onan muffler is a little larger diameter and a little longer than my original Generac muffler. It's made a little better than the OEM Generac. Sound seems to be about the same as the OEM. It was a good price and shipped fast.

So much better with this on, instead of a long pipe running up to the front of the right behind the driver's seat, gassing me out if I opened the window! just redirect the pipe to the rear, into the muffler and out next to the big exhaust pipe.

The media could not be loaded.  It is excellent quality, and made my project of reducing noise from generator substantially, very successful. Reduces tail pipe noise from 72 to 62 dB. Although I had to modify to fit properly as it was not intended for this application it was a fantastic addition to gen set.

Made my Onan nice and quiet!!

I like the fit,and this went on a Antique RV ginny

This worked perfect for my onan generator. It is quiet fits well.

Was not exact replacement for my style generator and had to revise the mounting method but has provided a sound reducing muffler for the generator.

Quieter than the old rotted out muffler. A bit longer muffler body. Overall length nearly the same. Did have to to a local muffler shop and have an reducing adapter since the inlet on this muffler is 1 1/2 inch. Thin metal. Unable to remove the moisture drain plug. In so tight I am worried I will damage the muffler. Saved money, as it is just a bit of $100 cheaper than the Generac muffler being marketed on Amazon. I painted the muffler with Utra High temp paint used on gas grills as the galzvinized finish on this muffler looks thin.UPDATE 08-13-2025 Over all this muffler is holding up. It is installed onto an 1989 Generac NP-52G gas generator installed in a compartment on my motorhome. The generator is ran and exercised under full load 15 minutes every week as required by the manufacturer's service manual. So the muffle had a good amount of use. The zinc finish it came with is corroded off. I have had to paint it twice with high temp paint. In the photo is due for a paint touch up. I live in the deep south so the corrosion is not me driving on salted winter roads. Do note the exhaust nozzle point straight out. So if at an slight angle, rain water might get in. I added a angle tip to prevent that. The db noise level has not changed, pretty much the same as when it was brand new.

Piece originale qu'il me fallait

It arrived very fast, well packaged and works like a charm. A few minor adjustments to allow for a tight piping fit and it's good to go. The best price I could find for this muffler and well worth it, Thank you very much.

Exact match to my onan factory one,Seams well built,The sound is the sameGood purchse

More expensive than after market but oh so much quieter. Worth the cost