I got this truck for free and a buddy and I are in the process of getting the 4.9L running again. To my suprise its a F250 with a 6600gvwr??? Never heard of it until now but it was FREE so I am not complaining.

What would I have to change to get it up to a "REAL" HD F250 gvrw??

 

I've never heard of a 6600 lb GVWR on an F-250. The standard-duty F-250 had about a 7,600 lb GVWR. In fact, until about '84 (give or take) that was what a 3/4 ton truck was. The heavy duty F-250s (and other makes) came out with GVWRs above 8,400 lbs to get around the new (at the time) limit requiring catalytic converters etc.

As far as what was different between a standard F-250 and an HD, the main thing I'm aware of was a full-floating rear axle in the HD while the standard still had an 8 lug Sterling (or Dana 60 back in the day), but it was semi floating. Not sure what else might have been different, probably springs, maybe more?

 

One problem is, no matter how much you beef it up with axles and springs it will still not be legal to carry or tow anymore than the weight rating listed on the sticker on the door post or any other weight rating plate ...

Oh you can beef it up and haul as much as you want, BUT, if you are involved you can bet the lawyers will clean your clock, or worse!!!

 

Don't know about your state, but in Washington you can register a vehicle for any gross weight above the current registered gross weight you want. You just pay the higher gross weight fee. You can also get trip permits for over weight vehicles. I think the only limit is the minimum number of tires required to support the load.

 

I didn't look up your state, but I did look up WI. Straight from the law book:

So they'll be happy to take your extra money, but you're not legally getting anything in return. I suspect your state is similar.

 

i totally understand your cynicism, but i would take that to mean that if you documented your addition of bigger rear end and/or brakes and/or springs, you would be legal.
of course, in the event of an accident, paying a lawyer to argue all these facts isn't cheap either. short answer : buy a truck that is already registered to carry the weight that you intend to carry.

 

Your GVW plate is 100% un touchable after purchase.. There is nothing, absolutely nothing you can do to legally change your weight ratings after new vehicle purchase. State legality loopholes notwithstanding, those ratings are a federal thing.

edit: ok, maybe absolutely no way is a bit harsh.. I just have never seen any ways proven. I probably should have said, AFAIK, as of right now, I know of no way to change your manufactured GVW/GCVW.

 

Ignoring the legality of the affair a dana 50 front 10.25 ff rear and a set of replacement springs is all I know to replace u joints maybe frame may also be different tranny cooler could be bigger

 

I must admit I hadn't gotten around to thinking about Johnny Law yet.

I am still curious how much difference there is between mine and every other F250 on plant earth.

In theory I would think I would have to get:
Full Floating Sterling Rear
Beefier Front Axle Beams
Beefier Springs Front & Rear
Bigger Brakes that came with above Axles
Drive Shaft
Tranny (I haven't heard that much about the M5R2 but the fact that it's a Mazda Tranny makes me think it's not that stout for heavy hauling.)

So what was the point of my truck being built with a similar rating of a 1/2 ton? Why put 8 lug axles under it?

 

What you have there is a heavy duty 1/2 ton and no it's not unique I have seen plenty in their day. Upgrading it to an HD would require replacing everything except the body.. frame, axles, suspension.. and that's not worth the trouble IMO. I say just get the thing running well and enjoy it, unless you got a use for an HD truck all you will accomplish with upgrading this one is make the ride harsh.

 

there was another guy on here with a 9th gen LD f250.
iv never seen one.
take a look at the frame in the front,where the front bumper mounts.does it have a crumple zone? im just curious is all.

by the 9th gen era the 300-6 probably never was a factory stock option in the f250hd/f350.it probably had to be special ordered or added.iv only seen one person claim to have a 92'+ f350 w/ the 300.that's kinda too bad imho as i think it was the best gas engine ford ever built.too bad it was reduced to f150's only (or the rare ld f250's) by this time.though,they would be pretty slow trucks no doubt in a heavy truck.....but still.sure beats the 8-10 mpg of the 460.

the hd version of the trucks all came with the e40d auto (or by this time,c6 as optioned) or the zf5.the mazda is too light duty for the hd trucks.it was too light duty for working the f150's hard too in my experience.

she is what she is.don't bother trying to change it.just run it and enjoy or trade it.

 

He has a 2WD, so no Dana anything front axle. I don't know if the standard F-250s used different Twin I Beams than the F-250HD or not.

 

I doubt the 2wd beams have any differences as far as ld vs hd

I would suggest you get rid of the Mazda transmission regardless of anything else