Is there any leeway on that first change or does it have to be done at exactly 5000 miles?

When I tried to get my 5000 mile service the Cummins Sevice center in Houston told me I didn't need it. I have the larger capacity filter and did not need a service until 75,000 miles. It's based on the serial number of the transmission. I was leery and so I verified this service bullitin on the internet and printed it for my files. I would assume that since your coach is newer than mine that you may also fall into this catagory but I would check with your Allison service shop to make sure.

According to my memory (not always perfect), there was something I read that said we had to get our first transmission service at or before 5000 miles. We were in the Coburg area and had the filter changed and all items on the 5000 mile checklist completed by Pacific Detroit Diesel Allison for $75.00. They were great to work with. You should check your trasmission serial number and warranty info to be safe. If you call an Allison service center they can advise you what needs to be done based on the serial number.

Click on the link in Route 66 Post here for allison info concerning fluid change intervals.