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Topic: muffler change today (Read 752 times) previous topic - next topic

muffler change today

Getting the trash can muffler replaced with a straight thru resonator today. Buddy of mine who knows his diesels, says 7 lbs of back pressure will keep the torq values peaked so I am having him add the resonator. I'll report back on driving and noise fun!
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: muffler change today

Reply #1 –
Post a few photos if you can.

jk
Jack and Cathy
1992 U280 Unihome 36' Build #4034
Cummins 8.3 /  Allison MT647/ PacBrake
Apopka, FL / Barre Center, NY

Re: muffler change today

Reply #2 –
Quote
Post a few photos if you can.

I second this. It's fun to see the different approaches to this deal.
jor
93 225
95 300
97 270
99 320

Re: muffler change today

Reply #3 –
Along with pictures. Have your lovely assistant positioned in the back with a cell video going on the way to and from the shop. I.E. A before and after. (if it's not to late)
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: muffler change today

Reply #4 –
To late. I walked home. My lovely assistant was on a conference call. Ha Ha
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: muffler change today

Reply #5 –
Yes a certain amount of back pressure is helpful
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: muffler change today

Reply #6 –
What model resonator? I might do the same.
1994 U280, Build 4490
Deming, NM.

Re: muffler change today

Reply #7 –
Quote from: dans96u295ft –
To late. I walked home. My lovely assistant was on a conference call. Ha Ha
You better take your assistant with you to pick it up and record the sound. Or we will toss wet Rigatoni at you. :))  :))
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: muffler change today

Reply #8 –
Ok. Soon as I hit the key, I could hear the turbo spool up and spool down . Soon as I pulled into the 45mph lane I felt more torq! It is still quiet but you can now hear the Cummins turbo. Sounds a bit nasty to be frank! Campgrounds won't know the difference. Next trip pulling hills I know, I'll report back. I'll post pictures soon! He had to cut all the old out from corrosion (hangers, bolts, clamps). $500 well spent. I'm up for hernia surgery so couldn't do it myself anyway. Highly recommend it!
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: muffler change today

Reply #9 –
You will adjust quickly. It will become the new normal
Tim Fiedler    2025 LTV Unity MBL on Order
2000 Chevy Tracker 2 Door Convertible 4WD Now lifted 4.5"
1985 Citroen 2CV6 Charleston
Murphy Rebel on wheels with 175HP Titan
Cessna P337
1980 48' Westport MY (!/4 Share)

Re: muffler change today

Reply #10 –
Noticeable torque increase.  Even more if you have the correct hydraulic fan controller versus my oem sucked 50 hp when the motor was warmed up every time
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: muffler change today

Reply #11 –
Try pics again
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: muffler change today

Reply #12 –
I hope that hanger isn't solid mounted from the rez to the frame above. Shouldn't it have a vibration isolator of some sort. Or am I just not seeing it?
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: muffler change today

Reply #13 –
It's rubber supported at the mount but there are 3 hangers. I'll keep an eye on it. Thanks
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: muffler change today

Reply #14 –
Quote from: dans96u295ft –
It's rubber supported at the mount but there are 3 hangers. I'll keep an eye on it. Thanks
Ok, I just wasn't seeing it.  ^.^d
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: muffler change today

Reply #15 –
Some in the past have found the old muffler full of carbon,how does yours look?
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: muffler change today

Reply #16 –
I didn't look as my muffler shop did the work. I saw it laying there and didn't say goodbye to the beast!
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: muffler change today

Reply #17 –
Forgot, My idle cam up appx. 200 rpm's as well. Old muffler had 125,000 on it and must have been partially plugged with carbon
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: muffler change today

Reply #18 –
Quote from: dans96u295ft –
Forgot, My idle cam up appx. 200 rpm's as well.

You need to have the idle speed set back to factory spec.

Your idle speed may be approaching the RPM where the Allison will not go into gear (to protect itself).  If this happens the shift pad will just flash when you try to put it in gear.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020
 

Re: muffler change today

Reply #19 –
Good to know. I believe in gear, 750 rpm is spec on the 8.3, I'll look it up. Thanks for the tip
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.