• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

Stoutness of the 7.5?


Soledad

New Member
Joined
Feb 19, 2016
Messages
90
Reaction score
0
Points
0
Vehicle Year
2003
Make / Model
Ford
Engine Size
2.3L Duratec
Transmission
Manual
I just picked up a 2003 XL 2.3L 2wd 5-spd manual regular cab and am currently learning the truck and fixing everything that needs fixing. It's got 130,430 miles on it and it's needing some definite TLC.

Any way, I've learned that it's got the 7.5 axle with 3.73's and open diff.

I've been contemplating on putting in a V8 & auto trans and was wondering if the 7.5 could handle the power increase? I'm not looking to take the truck drag racing or anything nor would it be used exclusively for rock crawling and etc. It would be used about 95% on street as a parts/home/trash runner, 5% light offroading and 1% generally just messing around.

The Explorer V8 I throw in it would be upgraded to make somewhere near 300HP (no clue on tq). I'm not looking for big numbers.

Oh and I'll be putting 31x10.5x15's tires on it too.

Could a 7.5 handle that or is it a must to move up to the Ranger 8.8 or Explorer 8.8? If I had any :icon_welder: skills I'd just go with an Explorer 8.8 but my little 120v Harbor Freight flux core welder probably can't put out enough heat to weld the spring perches and shock mounts and I know of no one or any welding shops around here to do the job.

Anyone run a V8 or high HP engine and 7.5 axle and live to tell the tale?
Right now I'm just looking into my options but the V8 will happen.

Thanks!
 


jeremysdad

New Member
ASE Certified Tech
Joined
Nov 19, 2014
Messages
354
Reaction score
3
Points
0
Vehicle Year
1993
Make / Model
Ford
Transmission
Manual
I had a 2002 that I bought new. 3.0 5 spd w a 7.5 rear. Spider gear and a retainer fragged in about a year.

Personally, I would find an 8.8 from a jy donor. Find one in a ranger and it will be a straight swap.

Good luck!
 

85_Ranger4x4

Forum Staff Member
TRS Event Staff
TRS Forum Moderator
Article Contributor
V8 Engine Swap
OTOTM Winner
TRS Banner 2010-2011
TRS 20th Anniversary
VAGABOND
TRS Event Participant
Joined
Aug 7, 2007
Messages
32,226
Reaction score
17,546
Points
113
Location
SW Iowa
Vehicle Year
1985
Make / Model
Ford
Engine Type
V8
Engine Size
5.0
Transmission
Manual
What are you planning for power with your proposed V8 swap?

Ring gear and spider gears are all you are really gaining with a 28 spline 8.8.
 

Soledad

New Member
Joined
Feb 19, 2016
Messages
90
Reaction score
0
Points
0
Vehicle Year
2003
Make / Model
Ford
Engine Size
2.3L Duratec
Transmission
Manual
Eh, I'm not looking for big power. I figure up to about 300HP from a '99-'01 Explorer 302.

I figure the higher TQ/HP and larger 31x10.5x15 tires may put the 7.5 beyond what it's capable of.
I just don't know "exactly" what it's capable of.
 
Last edited:

85_Ranger4x4

Forum Staff Member
TRS Event Staff
TRS Forum Moderator
Article Contributor
V8 Engine Swap
OTOTM Winner
TRS Banner 2010-2011
TRS 20th Anniversary
VAGABOND
TRS Event Participant
Joined
Aug 7, 2007
Messages
32,226
Reaction score
17,546
Points
113
Location
SW Iowa
Vehicle Year
1985
Make / Model
Ford
Engine Type
V8
Engine Size
5.0
Transmission
Manual
Ford became nervous putting a 200hp V8 in front of it for the 1986 Ford Mustang, the first year they got a 28 spline 8.8.

And a foxbody is both lighter than your truck and packs much smaller tires.
 

Soledad

New Member
Joined
Feb 19, 2016
Messages
90
Reaction score
0
Points
0
Vehicle Year
2003
Make / Model
Ford
Engine Size
2.3L Duratec
Transmission
Manual
Doh!! Now that I understand.

Do you think a 28 spline 8.8 out of a Ranger would handle it or am I looking at a definite Explorer 8.8 swap?
 

85_Ranger4x4

Forum Staff Member
TRS Event Staff
TRS Forum Moderator
Article Contributor
V8 Engine Swap
OTOTM Winner
TRS Banner 2010-2011
TRS 20th Anniversary
VAGABOND
TRS Event Participant
Joined
Aug 7, 2007
Messages
32,226
Reaction score
17,546
Points
113
Location
SW Iowa
Vehicle Year
1985
Make / Model
Ford
Engine Type
V8
Engine Size
5.0
Transmission
Manual
If you are going really use that power I would go Ex 31 spline. If you want to add disk brakes I would go Ex 31 spline so you would kill two birds with one stone.

If you do what you say you are going to do a 28 spline would probably be fine.

My 130k mile 7.5 never whimpered with me throwing my 200ish hp V8 at it though, they were together for a year. I mainly got my 8.8 for the limited slip... and I had it before I got the 302 just not installed.
 

Soledad

New Member
Joined
Feb 19, 2016
Messages
90
Reaction score
0
Points
0
Vehicle Year
2003
Make / Model
Ford
Engine Size
2.3L Duratec
Transmission
Manual
Thanks for the insight everyone. I'll go with an Explorer 8.8 and try and find someone to weld the spring perches and shock mounts.

Well, actually, that brings me to another somewhat related question; Could the 120V Harbor Freight flux core welder actually provide enough heat to weld on the perches and mounts properly? Exhaust is one thing (which I bought it for) but axle tubes are a whole other ball game.

You know what, I retract that question. I'm not good enough yet to weld something so critical. I'll find a place to do it.
 
Last edited:

BLOODBANE

Active Member
V8 Engine Swap
TRS Banner 2010-2011
Joined
Aug 7, 2007
Messages
1,119
Reaction score
19
Points
38
Location
Canon City, CO
Vehicle Year
19841994
Make / Model
FORDFORD
Engine Size
347, 4.oh
Transmission
Automatic
If you can find a FX4 Ranger, they came with 31 spline 8.8. BUT, tough to find... I ran a 7.5 for a little bit behind my first 302 in my 84.....

I did wheel it a little bit (Im not hard on equipment though). I had 32's on it in this pic with a Lock-Right. It held up, but like i said, I wasnt hard on the stupid pedal....
 

Soledad

New Member
Joined
Feb 19, 2016
Messages
90
Reaction score
0
Points
0
Vehicle Year
2003
Make / Model
Ford
Engine Size
2.3L Duratec
Transmission
Manual
Thanks Bloodbane. I'm lovin' that pic! Makes me miss my ATV'ing and 4wd'ing days when I lived in Colorado a few years ago.

Because this truck is 2wd, even with a locker I still wouldn't take it to places like that. Only level 1, 2 and maybe 3 trails for this thing. I haven't been wheeling here in the Cascades or Wenatchees yet so I'm not entirely sure what to expect.

I think I actually found a place selling a FX4 Ranger 31-spline 8.8 but the price is almost triple what a regular 8.8 goes for. So it would seem they know what they have.

In the long run though I think the Exp 31 8.8 will be the way to go. It gives me a little head room in case I want to up the power or get more bold in where I take it.
 

85_Ranger4x4

Forum Staff Member
TRS Event Staff
TRS Forum Moderator
Article Contributor
V8 Engine Swap
OTOTM Winner
TRS Banner 2010-2011
TRS 20th Anniversary
VAGABOND
TRS Event Participant
Joined
Aug 7, 2007
Messages
32,226
Reaction score
17,546
Points
113
Location
SW Iowa
Vehicle Year
1985
Make / Model
Ford
Engine Type
V8
Engine Size
5.0
Transmission
Manual
And if you ever need a shaft Explorer ones are much easier to find than FX4 ones. And if you want anything other than a Torsen you will have to get an entire carrier.
 

monstermazda

New Member
Joined
Sep 18, 2013
Messages
105
Reaction score
1
Points
0
Vehicle Year
1998
Make / Model
Mazda
Engine Size
3.0l
Transmission
Manual
You can put a 351w roller motor in there with the 99-01 302 heads and electric stuff it make the computer think it's a 302 but it's a 351 they both had the same deck hight if I remember correctly

Sent from my SAMSUNG-SM-G870A using Tapatalk
 

pjtoledo

Well-Known Member
Supporting Member
U.S. Military - Veteran
Joined
Oct 5, 2007
Messages
5,341
Reaction score
2,916
Points
113
Location
Toledo Ohio
Vehicle Year
20002005199
Make / Model
Fords
Engine Size
3.0 2.3
302 is 8.206, 351 is 9.48 or 9.503 early vs late.
 

85_Ranger4x4

Forum Staff Member
TRS Event Staff
TRS Forum Moderator
Article Contributor
V8 Engine Swap
OTOTM Winner
TRS Banner 2010-2011
TRS 20th Anniversary
VAGABOND
TRS Event Participant
Joined
Aug 7, 2007
Messages
32,226
Reaction score
17,546
Points
113
Location
SW Iowa
Vehicle Year
1985
Make / Model
Ford
Engine Type
V8
Engine Size
5.0
Transmission
Manual

don4331

Well-Known Member
V8 Engine Swap
Joined
Sep 6, 2013
Messages
2,007
Reaction score
1,329
Points
113
Location
Calgary, AB
Vehicle Year
1999
Make / Model
Ford
Engine Type
V8
Engine Size
5.3
Transmission
Automatic
I'm going to question the fox body 'stang being lighter than Ranger/narrower tires. :)

The '95 Cobra I got my rims off crossed the scales @ 3,458lbs; 1,522 of that on rear axle. My Ranger tips scales @ 3,549lbs; 1,477 of that on rear axle. (Both weights are with me in driver's seat). So, Mustang is 50lb heavier on rear axle and my Ranger has a hard tonneau. Without tonneau, Ranger is lighter overall than Mustang and only has ~80% of weight on rear wheels that the car does.

Mustang had 245/45R17s, Ranger 235/60R15s. Just saying. :)

You don't have to do any welding. Order a set of DJM Suspension lowering blocks for an F-150, and use them to put the spring perches on top (opposite of how they were intended to be used).

The 7.5" in my '82 'Stang ('69 351W 4bbl engine) lived largely because I simply couldn't hook up well enough to break anything, but then again it had 3.08 gears. Your 7.5" probably has 4.10s...
 

Sponsored Ad


Sponsored Ad

Staff online

Today's birthdays

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Truck of The Month


Kirby N.
March Truck of The Month

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store


Sponsored Ad


Sponsored Ad

Sponsored Ad


Amazon Deals

Top