Rear diff swap???
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Tuned
Joined: Jan 2005
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Rear diff swap???
Hi guys,
I have a 99 2wd 2.5L reg cab(el cheapo model) with 7.5" axle and 3.73 gears. I would like to go with slightly bigger tires (235 75 15?) but I mainly want to get into some sort of limited slip. If I went with bigger tires, I think I'd like 4.10 gears also, to slow it down a bit.
I am currently thinking I'd like to find a complete axle somewhere. I could fabricate new mounts, etc if necessary, but would be leery of adjusting backlash,etc.(heard it's not a DIY kind of job). It would be nice to just bolt it in, though!
Do you think I'm crazy or what? What kind of donor vehicle should I be looking for. Any other ideas??
TIA, Jim
I have a 99 2wd 2.5L reg cab(el cheapo model) with 7.5" axle and 3.73 gears. I would like to go with slightly bigger tires (235 75 15?) but I mainly want to get into some sort of limited slip. If I went with bigger tires, I think I'd like 4.10 gears also, to slow it down a bit.
I am currently thinking I'd like to find a complete axle somewhere. I could fabricate new mounts, etc if necessary, but would be leery of adjusting backlash,etc.(heard it's not a DIY kind of job). It would be nice to just bolt it in, though!
Do you think I'm crazy or what? What kind of donor vehicle should I be looking for. Any other ideas??
TIA, Jim
Posting Guru
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Some/all of The v6 rangers had an 8.8 rear in those years. The easy way is to swap out the whole rear housing/brakes. A 410 rear was also available and is a direct change out for your 7.5" rear. The only thing that may need to changed is the driveshaft. Check the rear tag info in the tech section here to find the right rear. Any yard will be able to match you up with a good rear.
Dave
Dave
Last edited by Dave257; Jan 19, 2005 at 09:37 PM.
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Joined: Nov 2004
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From: Southern MD
Originally Posted by guessrow
Hi guys,
I have a 99 2wd 2.5L reg cab(el cheapo model) with 7.5" axle and 3.73 gears. I would like to go with slightly bigger tires (235 75 15?) but I mainly want to get into some sort of limited slip. If I went with bigger tires, I think I'd like 4.10 gears also, to slow it down a bit.
I am currently thinking I'd like to find a complete axle somewhere. I could fabricate new mounts, etc if necessary, but would be leery of adjusting backlash,etc.(heard it's not a DIY kind of job). It would be nice to just bolt it in, though!
Do you think I'm crazy or what? What kind of donor vehicle should I be looking for. Any other ideas??
TIA, Jim
I have a 99 2wd 2.5L reg cab(el cheapo model) with 7.5" axle and 3.73 gears. I would like to go with slightly bigger tires (235 75 15?) but I mainly want to get into some sort of limited slip. If I went with bigger tires, I think I'd like 4.10 gears also, to slow it down a bit.
I am currently thinking I'd like to find a complete axle somewhere. I could fabricate new mounts, etc if necessary, but would be leery of adjusting backlash,etc.(heard it's not a DIY kind of job). It would be nice to just bolt it in, though!
Do you think I'm crazy or what? What kind of donor vehicle should I be looking for. Any other ideas??
TIA, Jim
Trying to remember from 'the ole days' - when the tire size increases, you are changing (theoretically) to a 'higher' ratio (lower number gear).
By swapping out the 3.73 for a 4.10 you won't gain anything (much). The only gain would be IF you kept the same size tire/wheel combination.
Yes, you would get out of the 'hole' faster, but, the 'top-end' would be less, because of the hp, torque and gearing, only if the tire diameter is the same, or smaller. (I didn't see what the original tire size was.)
Anything more than 4.10s and that 4 cyl will be huffin' and puffin' in short order.
The 235/75-15s might not make any difference, in which case, it would all go back to the LS option.
Thread Starter
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Tuned
Joined: Jan 2005
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original tires were 225 70 15
so the 235's wouldn't be a big jump. I'm driving on 225 75 15's now and it seems just a little too fast. I think the 4.10's might be the ticket. Should I be looking for another 7.5" rear or 8.8" rear? If I forgot about the LSD, is it possible to regear by current axle with 4.10s?
cost and lsd are the other factors in this equasion.
Thanks, Jim
cost and lsd are the other factors in this equasion.
Thanks, Jim
Logistics Pro
Joined: Nov 2004
Posts: 4,562
Likes: 2
From: Southern MD
Originally Posted by guessrow
so the 235's wouldn't be a big jump. I'm driving on 225 75 15's now and it seems just a little too fast. I think the 4.10's might be the ticket. Should I be looking for another 7.5" rear or 8.8" rear? If I forgot about the LSD, is it possible to regear by current axle with 4.10s?
cost and lsd are the other factors in this equasion.
Thanks, Jim
cost and lsd are the other factors in this equasion.
Thanks, Jim
I've don't have much experience with the different size(s) of rearends in Fords, such as 7.5 vs 8.8. I do have quite a bit of experience with other rears, though.
(In my younger days.)
IF you could find a 8.8 rear, I don't know why it wouldn't bolt up. If this is wrong, I stand corrected. (Other input????)
As for installing the gears for 4.10s, you MUST set them up correctly. The pinion depth needs to be right, the ring gear 'backlash' has to be right, otherwise you will either go from a little noise in the rear up to galling teeth, causing the metal to lose their heat treatment, all the way to include breaking teeth on the gears.
IF you could fine a junkyard with 8.8 set-up with 4.10s already installed, that would be the way to go.
There is always "Currie". They can build you a rearend, set-up and ready to go. (That's $$$$$$$$, though.)
Last comment. . . as for the 3.73s being 'too fast', just let-up on the gas.
(Sorry, I HAD to say that.)
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""IF you could find a 8.8 rear, I don't know why it wouldn't bolt up. If this is wrong, I stand corrected. (Other input????)""
Yes it is a direct bolt up. Look for an 8.8 out of a v6 ranger with 4.10 LS and good brakes and it will replace the 7.5 housing/diff/brakes/etc. Its about a 3 hour job with a lift. A little longer with jack stands. Also manny more 4 wheel drives had the 4.10 in them, they will also fit.
Dave
Yes it is a direct bolt up. Look for an 8.8 out of a v6 ranger with 4.10 LS and good brakes and it will replace the 7.5 housing/diff/brakes/etc. Its about a 3 hour job with a lift. A little longer with jack stands. Also manny more 4 wheel drives had the 4.10 in them, they will also fit.
Dave
