Hi guys, I've been researching here and elsewhere and I haven't found too many favorable opinions on the 7.5 rear end. The only performance upgrades I will be doing on my '86 will be the HO Upper Plenum/TB/EGR Spacer swap and probably a "performance" ler on the stock single exhaust. I do like doing the occasional burnout or powerslide and the car may see a few trips down the 1/4 mile. Do you think the stock unit would be sufficient for this? Are there any parts that will make this unit stronger? I don't even care about a T-Lok(I may consider 3.73's in the future), I just want a reliable axle that can withstand some fun.
Thanks.
I think without slicks that 7.5 will handle just about anything you throw at it. Remember, the Mustang didn't get the 8.8 until '86 or so, and the Capri never got it at all...
Traction lock will help it live longer (one wheel peels will chew up the spider gears). There used to be a "girdle" cover available for the 7.5 which added strength, but I don't imagine it added strength to the weak spot. I am no expert on rear ends but if I were to guess I'd say the weak spot in the 7.5 would be its pinion gear and spider gears and shaft.
To hell with trak-lok. Get a full locker, some aftermarket axles, a rear main girdle and be done. The locker I have in mind e is rated to 800 ft lbs of torque. The spider gears are the weakest link. The full locker eliminates them. American Muscle sells a rear girdle for the 7.5 as does LPW.
If I had to do it again I'd go 31 spline instead of sticking g with 28. Other than that I can't complain.
I've never had issues with my 7.5's. The only time I had an issue was when I rebuilt a rear end and took out the carrier and reinstalled it with new crush sleeves and bearings. I didn't get the backlash right or something and it ate up the gears. I've learned to just leave the carrier in place and not change the bearings unless it's needed.
I haven't broken one yet. the v-6 stangs ran them forever, even the.250+ hp ones.
Thanks guys. It sounds like for close to stock power levels I should be good, even with having some fun. From what I read online I'm expecting for the rear to grenade on a hard take off. Lol
If something happens I'll just have it rebuilt stronger. But this is a cruiser so I really don't see a need for an 8.8 upgrade if this axle is sufficient.
You can upgrade cheap by pulling a trac lok and gears out of a ranger
I did it for my buddy with a v6 stang
Would I have to upgrade the axles if doing this?
There 28 spline you can use your axles
All 2.3 mustangs were also 3:73 gears and traction lock, if your fine with a 7.5". That's what i plan to do later.
Is limited slip the same as trac lock? My 84 Turbocoupe has 3.45 gears and I believe limited slip. I am going to change fluid and seals soon on it.
Yes a trac lok is a limited slip
Each munufacturer had their own name for a limited slip rear end. Ford was Traction-Lok. Chev and GMC was Positraction. Chrysler was Sure Grip.
Not even close to truth.
I can vouch for my '87 2.3/T5 Stang as having an open diff. I'd have to go out to the shop to see the tag on the rear, but I can assure you and anyone else it's nowhere near 3.73. I replaced it with a 3.55 8.8 with trac lock from another Mustang. It does have 3.55 gears...they've been changed, it's stamped into both the ring and the pinion..
When I put that rear into my Sport in 2009, I noticed it was a 3.55 swapped rear when filling it with new diff fluid.
Compared to the anemic 7.5 the 3.55 8.8 makes the "WussStang" haul ass....it'll be MUCH more fun once I get my 5.0 finished and dropped in..doing some much needed shop upgrades while I have free time and a bunch of stuff cleared out.
I've checked 3 or 4 and all I've seen were 3:73 with traction lock. Ill check a couple next time. i hit the yards
http://www.dfwstangs.net/forums/showthread.php?p=6341925
here at least one guy says a 7.5 he borrowed from an 88 2.3 coupe had 3:73's in it.
from what i can tell, traction lock was optional on the 2.3 and manuals had a 3:45 and autos had a 3:73. Not a lot of the links are very trust worthy though.
from what I've checked, 2 or 3 4 bangers had 3:73's and traction lock. i was under the assumption they all did.
i personally don't see a need to upgrade from a 7.5 until i blow one up, and out of the 7 or 8 cars I've had, none have. i don't think any have been traction lock though.
Of all the 2.3 cars I've ever seen (quite a flipping few, actually) the ONLY one that has had a trac locked rear is mine...and I swapped that one in.
I don't know about the SVO/Turbo GT stangs of 20+ years ago, but I can say that I've never heard of an aero 2.3 stang having such an equipped 7.5 rear..not saying it's not possible, but I've never heard of them.
I've never seen trac lock in a 4-cyl Mustang either. I have seen plenty with 3.73 gears though
I finally pulled the cover off of my 7.5 with 3.45's. I think I found the source of my noise. I'm missing about 4 complete teeth on the ring gear. 2 missing in one spot and about a 1/4 way around the gear another 2 are missing. Today wasn't a good day. Not only that but the new clutch I put in isn't working right. I'll probably have to pull the tranny again.
If you are set on keeping the 7.5 then the ranger gear and trac-lok swap is pretty nice. Knock the rear end apart, change the axle bearings & seals, and inspect the bearing surface on each axle. I would take the Ranger parts and your rear end to someone that can setup the gears. I leave the axles out as I don't like them messing with it as its just more work they have to do when I can knock it out. Get a complete rebuild kit like the RaTech 304K or 3006K if you want the axle bearings as well:
http://www.ratechmfg.com/fordstandard.htm
You will also need a trac-lok rebuild kit but finding one for a 7.5" is not as easy as the 8.8"
http://www.ringpinion.com/b2c/ProductDetails.aspx?ProdID=1039&Product=YPKF7.5-PC&Brand=Yukon_Gear_and_Axle&ShowAA=True&Year=1993&Model=Mustang&DriveType=Rear%20Diff%20-%20RWD&DiffId=159&Source=DiffWizard
http://broncograveyard.com/bronco/i-92241-ford-7-5-trac-lok-clutch-kit.html
Take the trac-lok kit to the person setting up the rear end as well so its all done when you pick it back up. I have seen people charge anywhere from $100 to $200 to set one up but you may know someone who will hook you up.
Darren