Welcome to irv2.com! That sound can mean several things. Don't wait until anything worsens, get your RV to a Allison authorized repair center ASAP!
The
Allison FAQ page may be of use, but an Allison authorized repair center will read the computer codes and narrow the focus to specific areas of concern.
How long since you've had your transmission serviced and inspected? If the transmission is slipping the computer will cause a "limp mode" condition, limiting engine RPM, speed and gear selection until the fault is rectified.
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2000 Winnebago Ultimate Freedom USQ40JD
, ISC 8.3 Cummins 350, Spartan MM Chassis. USA IN 1SG 11B5MX,Infantry retired;Good Sam Life member,FMCA.
" My fellow Americans, ask not what your country can do for you, ask what you can do for your country. John F. Kennedy