Chinook RV

Interesting service bulletin about body sway in early models due to only having a few leaves in the rear springs.

My 92 chassis indeed only has three leaves in the rear. Thinking of replacing with the later nine leaf version.

That's an interesting find. Kinda makes a person wonder how many TSB's are out that that one hasn't read yet

Just out of curiosity I looked at a photo I'd taken that included my rear leaf springs (I know my year is well after those included in the TSB, but after reading it I was curious). Mine does have the 9-leaf springs that are cited as the remedial "action" in the TSB.

I see they say your year could have either 3-, 4-, or 5-leaf springs. Since you only have the 3-leafers it seems you'd experience a noticeable difference with the 9-ers. (Or go for broke and get the parabolic springs )

Durn.

If the original owner had the Bumper-to-bumper warranty, it would've been covered for free if they'd taken it in

I'm torn between adding a spring helper, getting a spring shop to add a few more leaves, replacing with the later nine-pack, or using a sway bar instead.

Meh. It doesn't really sway enough to force me to do anything, so any change would be more like icing on the cake for me

Related: SD Springs has a product chart using the spring code from your Ford door VIN label.

http://www.sdtrucksprings.com/ford-spring-code-listings

My code is N4J, so the rear springs are code J, and sure enough under the + E-Series Van link on that page, it cross references to a 3 leaf spring, with capacity of 3450 lbs per side.
Btw, my axle code is E2, which is a Dana 70 HD limited slip with 7400 lb capacity and 4.10 gear ratio, which is the standard setup for an E350 cutaway (limited slip was an option).

http://www.blueovaltrucks.com/tech-arti ... r-sticker/

I believe the E450 used a wider Dana 78 (80) with 4.56 ratio.

FWIW My wife and I bought a brand new Tioga Montara 24' motorhome in 1993 on an E350 Chassis. I thought it sat low in the back and the first time I drove it at night I had all kinds of people flashing their lights at me like I had high beams on. The front end also seemed to wander a bit. I took it in to a local Ford truck dealer in Seattle that specialized in commercial vehicles. They ended up replacing the leaf spring packs and it solved all issues. This was done under warranty within 6 months of new. I don't remember the specifics as it has been many years and I threw the records away during our recent move.

Well that explains a lot.

When I got mine, it was terrifying to drive. They guy I bought it from said it doesn't really like to go over 65. We didn't have an area to test it any faster so I just thought he meant that it doesn't get good mileage. The first time I hit 70, it set up a resonant sway which scared me half to death. As soon as we got home, I bought a hellwig sway bar andnew shocks all around. I couldn't believe this thing existed like this for around 20 years driving the way it did.

It's a bit stiff now, but no more wobble.

My cutaway has a build date of 9/93, it's registered as a 94, and the coach build date is 11/93. Door tag lists the BN46 springs, they have 9 leaves, and there's no rear sway bar. The handling seems fine (for an RV). Wish I had an LSD. I've been stuck a couple times; camping on the beach is just too tempting. Might get an air locker. Happy Thanksgiving to you all.