Cracked Cab

Are you sure that crack was there before the window replacement? That looks like just about the spot they brace the little pry bar to get the old window out. If they didn't put some sort of backer along the roof first, they may have caused the crack. I can't tell if you have rust along the edges of the steel or not.

At first I thought you were talking about cracked crab and I was getting hungry.  Sorry to say I was wrong.    I would be looking into having a shop make a 1/4' (?) thick horseshoe shaped fabrication that followed the cutaway of the cab roof.  Then I would through bolt it all the way around to the cab roof, and maybe the cap??  Of course it's really hard to know how much work this would really be with the cabinets and all, and without actual standing in front of one.  Some manufactures actually construct their RV like this, wonder why....

Like you, we had more than our fair share of problems with our PC.  They make a nice RV but we got a dud.  I repaired it to better than new condition (really, it was better than new....) and sold it.  Keep in mind: (1) Its' a great time to sell an RV.  (2) It's a good time to buy a new RV, but the good ones are over a year out.  (3) It's a bad time to but a used RV (see (1)).

Good luck.

My previous 2 motorhomes were on the Sprinter chassi. Mercedes is very strict on what RV manufacturers can do to the chassis, they won't even allow drilling holes or even welding on the frame. As a result the motorhome has to be designed to fit the chassis. The manufacturers take the Ford and cut the frames, cut sheet metal lengthen wheel bases, weld where ever they want with no regard as to what they're doing to the integrity of the chassis, I can't run my PC over 60 mph because I have a hum and vibration in the rear end. I've rebalanced tires, had the drive shaft balanced, it wasn't out of balance. I had a heavy duty truck repair shop look at it, he said the cutting and lengthening of my frame was the worst he'd ever seen. He said it didn't look strong enough to drive. This whole thing is a just a big expensive mess.

We had the same problem with our 2910. Everything between the transmission and the differential had to be cut out rephased, re-supported, and replaced. That fixed it.  The Ford garage had to bring in a driveline specialist to do all the work.

My 2 cents.  And I’m using SWAG here big time.  I go along the line of WillLoyds route. The one caveat I’d throw out there is check into one of those shops that do major car restorations and body chops etc.. If anyone could fabricate a replacement of that cutaway roof and have it structurally sound my bets on them.  Now the cost I would have no idea but cheaper than replacing the entire cab I’d assume.   

Again, I’m just throwing out an idea. Could be the worst idea ever.

We had the same problem with our 2910. Everything between the transmission and the differential had to be cut out rephased, re-supported, and replaced. That fixed it.  The Ford garage had to bring in a driveline specialist to do all the work.

Now and then on other RV forums, I have read about issues from adjusting the wheel base through frame extensions.  It is sad that the companies who are licensed and approved by Ford to cut and expand the main frame & wheel base, are doing shoddy work.  That should never happen.  A Ford employee should inspect every chassis modified in this manner.

One thing I always appreciated about our PC was that the frame was not modified in such a manner.  Phoenix worked with the original 158" wheel base for model 2350, but it came at a sacrifice in weight distribution.  The rear axle carries a lot of weight.  The front axle could have handled a lot more weight, so much that I replaced the front coil springs with softer ones.  Everything has it's trade-offs.

Sprinter frames can't be modified due to the lighter gauge, high tensile strengh material. Same with Ford Transit. But that only applies to the chassis, not the cab roof structure.

Sprinter frames can't be modified due to the lighter gauge, high tensile strengh material. Same with Ford Transit. But that only applies to the chassis, not the cab roof structure.

Agreed.

The frame structure of the Sprinter cannot be stretched, drilled, or welded to.  It is built on the concept of a unibody.  Any frame damage immediately "totals" a Sprinter chassis because it cannot be repaired.

Here are some pictures I took of a Sprinter chassis at the Chicago auto show.  I understand everything is glued to the frame.  Mounting brackets and such are welded together on the side, then glued to the frame.  The frame gets it's strength through the "box" structure.  Any disturbance to the structure and it quickly looses it strength.  I am not putting this concept down, only sharing what I understood.