Right now I'm running on 315/75/16s (35s) f250 7.3 IDI turbo, slightly turned up pump, Zf5 spd, airbags in the rear. I'm wondering what the stock gearing is on these axles. I heard 4.10s? I haul a 4 horse trailer with horses and tack every once in awhile and would still like to be able to do so, however I've been considering a 6" lift and 37s as my next set of tires just for grins and giggles. I know the bigger the lift/tires of course hurts everything (mpg, power, towing, etc.) but would I still be able to pull a 4 horse occasionally? This is just something I've been kicking around and wanted to get your guys' thoughts.

Thanks

 

Lifting a ttb (250) front end is far from ideal, especially as much as 6". You would more than likely be looking at a Dana 60 swap which will net 1k+. 37s are a lot of tire, you could probably tow with it but with added strain on your clutch while maneuvering.

My opinion is no, if you really want 37s do a 1ton (d60) swap. The only benefit of 37s is military surplus tires are dirt cheap.

 

I know how sucky it can be to lift a ttb. But don't they make offset camber nuts to accommodate a lift and make them aligneable? Or is the only option a d60 swap? Any thoughts on how the truck would do power wise on 37s?

Thanks again

 

yea like plumcrazy said .. you can do it but you would need to make drop brackets for the ttb and likely a crazy steering linkage system .. unless you do a solid D60 swap and a couple extra chopped spring pieces ..

as far as towing with 37's .. i don't think you would have any problem at all .. i run 35's also on stock ride height .. and load it waaaay up on 3.55 never had anything near a problem pullin' ..

some say over 35's and you'r PS pump has a tough time .. i can't say first hand .. mine does 35's no problem .. i was looking the other day at just this myself ..

as they are no longer making bfg ko's new in 16.5 .. eventually i will exhaust my supply of used rubbers .. so i will eventually have to make the switch to ko2's .. and the 37 will require suspension adjustments .. while the 35x12.5 will fit the diesel without modification .. and they are now making a load range E in that size .. which is what made the decision for me .. when i do upgrade to the ko2 it will be .. BFG50022

because if i get another idi and i wan't to swap wheels i could just swap without any other issues .. but the 37's are nice .. just the easy fit and extra load range made the factor for me .. can't wait till i need new tires !!

 

Yea I run 35s right now and tow fine. But 37s is a lot of rubber.. Will my stock gearing be 3.55s as well then?

 

i have 37s and drove for a few weeks with 3.55s before swapping in my 4.10 axle. no way i would ever stay with 3.55s even without towing. waay too sluggish. 4.10s are perfect for all round use with that tire size and a ZF5.

 

ohh .. as far as axle gears look on the door tag .. let me grab a screenshot ..

and .. although they do make ofset camber suspension bushings .. they won't go to the angle that would be required for 6in lift .. and even if they did .. it would be a very poor radius of travel for the wheels and would ride really bad ..

not that it's not doable .. i will do this myself at some time .. as i already picked up an extra set of front spring leafs .. gonna add one and a few cut leafs and drop a spring bracket lower ..

i am still gathering parts .. will have to grab an extra set of motor mount ttb 'ears' and cut one and weld the other to them .. this way it won't require new bushings at all .. as i will drop the spring ends as well as the pivot points proportionally ..

cut and weld a robust drop arm extension .. and build a 'H' frame steering linkage system ..

so .. yes it's possible .. and if your a good fabricator / welder .. i say go for it .. but it's just not as easy as plugging in a few degrees offset bushings and getting it to drive well ..

these ttb trucks have a 'bad lift reputation' because people have tried just adding a spring and an offset bushing and the already marginal steering and springs ride like a buckin' rodeo bronco .. with some modification it can be done up nice though ..

 

axle codes

 

My 4 door bronco has 37's with 4.10 gears. It puts me back to 3.55 ish but more rotating mass.
Yes the e4od has a higher overdrive but I definitely think it scoots this 5 ton rig around pretty good! If anything spring for 4:30:1. Better ratio for everything on 37's