Question Gear Ratio Mixing

[apsnla]

i just recenty upgraded to a 2000 F-350 crew cab 4x4 with the 7.3L turbo and the 8 foot bed. ... its a clean truck engine runs great its a mother in the parking lots though. it had 200k when i got it andwas missing a few things ( muffler and exaut past it, head unit and speakers,key to the locking nuts(extra thanks to who ever dicided to take that with them it took forever to find one))but i got a GREAT deal on it. Needed to replace the locking hubs and happend to meet a mechanic who had just replaceed the dana 60 front axle of a 04' f-250 with 40k on it ( the track bar bracket that's welded to the axle was broken had the piece though sheered it right off not even bent). really only wanted the locking hubs off it but he said i could have the whole thing for $100 to get it out of his shop. SOLD...beats the $350 apiece the dealer quoted me and i get a nother dana 60 out of it...cool. so while replacing the locking hubs i had a wonderful surprise powdered rust and needle berrings filling one of the hubs. and so now i'm thinking dam glad i took the whole axle....one problem though...it's got a 4.10 gear and mine is a 3.73. now in my head that seems like it would cause some sort of a problem in the transfer case cause after a few revolutions the front axle would be draging since it's not spinning as fast...right? but i was just talking with one of my neighbors and he said they used to put jeeps and trucks together all the time when he was growing upwith different gearing....is that ok i'd really hate to screw up a perfectly good transfer case to save money on the axle...i know i could have the geering changed but that can get kinda costly too since i now i cant do it...any help would be greatly appriciated.

 

[keanoknick]

DO NOT mix gear ratios, you will tear up your transfer case.

 

[groundhawg]

There are certian instances where someone will use two different ratios, but this is usually in an offroad only vehicle.

For most people, especially those that are going to use the truck on pavement, then the ratios need to be either matched or VERY close...for instance, a 4.09 and a 4.11 used together would be OK, but much more than that could cause binding.

It's hard to say without seeing it, but it sounds like your unit bearing might be bad. There should be no need to replace the entire axle housing for a bad bearing. You just need to figure out exactly which one is bad and replace it.

If you can, get a few pictures of it and post it here...that might net you a bit more help.

No offence, but you might try to break up the sentences in your post some so it's more easily read. That single giant paragraph started to make my eyes hurt while I was reading.

 

[95_stroker]

Dont mix ratios, you'll tear up the x-fer case.

 

[TampaDieselFX4]

I ran 5.38's and 5.29's with 35" tires on a Off-road rig. worked fine. But the ratios you mentioned are WAY WAY!!!!! off from each other. DO NOT USE different ratios. 3.73 is your ideal ratio for 99% of folks. I have the OEM 20's and 275 GY's and love the 3.73 combo.

 

[yukondiesel]

If you've got it out and laying in front of you, now is the time to change it. Are you happy with your 3:73? the gears set shouldn't be that expensive (you need the ring AND pinion for that change, I think). If you find a good set up, used and have it done, it should be less than $300 to $400 total, and that might be on the high side, depending what you pay for the set-up. I know you said $$ were tight ( I understand THAT!), but you will never have a better time to do it. Be aware , also that locking or limited slips for the front axle can present issues, so check that out as well...Good luck...Joe