Full Float Time!

eddyturn · 11-07-2022, 03:48 PM

Hi any and all of you axle pros - I need some advice before pulling the trigger on a full float rear axle. Van is a 2014 E350 V10 cargo SMB 4x4 conversion van with a semi-float RSC rear axle. Current axle had bearings go out and mess up the axles in 2017 which were replaced under Ford warranty. In 2021 on a trip to Baja the driver side bearing went out and carved up the driver side axle along with it. Got that corrected in Baja and it did great getting us back to the US then down to FL and we had it all gone though in May once we got back home to Colorado. All seems good now but we will be traveling to Baja again then maybe to Wyoming/Montana and we don’t want to risk any problems as the van weighs in at about 10.2 fully loaded up.

I have read many threads (thanks to JoeH and carringB and others) and gathered enough info to be dangerous. I have pretty much zero mechanical aptitude so I get that from all of you. So now, I need to know which axle to get and I have it narrowed down to 2 choices from a fairly local supplier in NM. They can get me a Dana 70 from a 2008 with the 10.5 4.10 gears for about $1500 shipped to my shop in Durango but my shop kind of frowned on the D70 option as he has not done a D70 conversion. He would rather to a Dana 60 full float and the supplier has one for $500 with the 4.10 and 9.75 sized gears on hand from a 2006 vehicle.

Don’t know what trucks/vans these came out of but the guy at the parts recycler seemed to know the axles pretty well. Price is not really too much of an object as we just want to get this one done right.

BTW, I am scheduled to get new springs and shocks installed end of this week in Grand Junction by Alcan Spring. He seems to have learned quite a bit about these vans and has already done some for other owners.

Any input from you guys would be appreciated for sure.

carringb · 11-07-2022, 06:25 PM

The 9.75” FF will work if you don’t tow heavy, but your tone rings (really more of a band) will need to be swapped so tooth count matches, since the ‘05-‘08’ RSC axles had a slightly different tooth count.

Since you have 4x4, you might want to consider a Sterling 10.5”, then you can ditch the wheel adapters, and have a matching bolt pattern all around. U-joint off-road sells a spring perch kit. Your rear left shock has probably already been relocated if you have the TF tank. You’d need a 2012+ for RSC compatibility.

arctictraveller · 11-07-2022, 08:17 PM

I swapped in a D60 FF due to my concerns about axle capacity. As you know, when a bearing goes, it can eat the axle to the point where it breaks, causing the wheel to come off. I think your wise to upgrade, and the D60 should be a pretty easy swap. As for Alcan spring, i think they have a nice manufacturing facility and the chances of getting exactly what you want are good. Just be sure to be as clear as possible what your trying to accomplish such as multiple progressive leaves, individual pads between the leaves, a stated ride height (take photos before and after) correct spring weight (be sure to weigh each wheel when fully loaded if you can, sometimes there is a big difference from side to side) etc.

eddyturn · 11-08-2022, 10:15 AM

cB, thanks. Chris at the Ujoint said the Sterling would not work for my Sportsmobile or maybe it's just that his version of the Sterling would not work for me. I'll look into that one too as the local shop wanted me to do a Sterling as well.

REF · 11-08-2022, 10:47 AM

Not to take anything away from Chris, but check in with Justin at UJoint CO. I think I recall your shop in Durango is Built to Last? They did nice work sorting some other mechanics shoddy work on our rig when we were in the area, and were pretty knowledgeable.

eddyturn · 11-08-2022, 11:29 AM

Yes, Rick. BTL is my shop in Durango. I spoke with them last week on a plan and think I will see him today for more idle chit chat. Thanks.

aarcaris · 11-08-2022, 11:55 AM

I just did a sterling 10.5 swap into my 2013 RSC equipped van with relative ease. The donor axle was from a 2016 Ford F250 truck bed style truck and it was swapped into my 2013 E250. ABS sensors are plug and play, brake lines required some slight modifications, and the parking brake was pretty simple to set up. No issues with ABS or anything else so far. Still working on the break in process and will post more details and pictures in my build thread once I have some time to compile it all. I would consider looking at a sterling swap if you're looking for a full float option.

carringb · 11-08-2022, 02:11 PM

UJOR rear Sterling axles are built for non- RSC vans, using an ‘05-‘07 spec axle. They used to sell a spring perch kit but I don’t see it listed anymore.

eddyturn · 11-08-2022, 04:07 PM

The one thing about swapping to the Sterling is bolt pattern from what I know but maybe that is a older issue. Would the bolt pattern on the newer Sterlings be the same as the front Dana axle?

shenrie · 11-08-2022, 06:32 PM

^^^ depends. Does smb leave the f series axles 8x170 and add a rear spacer (8x165 to 9x170) to change the bolt pattern to match the front axle? If they do, that’s perfect. The sterling 10.5 has a wider footprint than the e series and spacers combined. The 10.5 I bought from a 2005 f250 for my 03 gave me the exact footprint I wanted with no spacers.