Thank you for the response Lance. I was reading back through the last couple of post and feel that my answer back to Bob might have sounded harsh, if it did that was not my intent and hope it wasn't taken that way.

To mock everything up I'm using the upr Teflon lined spherical. They are not easy to get in or out but are easier than the rubber bushings. To get the steel outer ring on the spherical joint (SJ) I had too freeze the sj and heat the ring for a nice tight fit, to say the least they are not coming apart anytime soon. To get the sj into the housing the fit is tight enough that you have to lightly hammer with a socket. Then tighten nut down and in my opinion this is not going anywhere. Upr says to put blue loctite on nut.

Just to see how it is and since it would easier to change I might try the upr sj first but that will be decided later.

Brent you and i know each other better than that. The only way we learn is asking opinion and forming our own. There are no books out there with the answers, it's trial and error for the most part..
Yes Delrin, a material that is equivalent to steel in wear quality, requires no lube per, should transfer NVH better than rubber , better than Teflon. Teflon I think has it problem with being a softer material, is less tolerable to dirt, water and wears much faster than delrin.
The front LCA and front UCA bushing are white Delrin, same bushings on the car for 24 years. Last time the front suspension was 100% out of the car, 2018, I replaced all the ball joints and bought new Delrin washers from Global for the LCA location. The sleeves were still good, they take the brunt of the wear. Because i was moving the LCA pivot points at all four LCA locations to move the balljoint forward 3/4" I thought new delrin washers would be nice to have.The old washer showed some wear but the location they live in is one of the worst places to survive in a car.

My mechanical clutch linkage is rod ends, tried several quality ends, QA1, Viking, think the 2nd set way back then was an FK, all were teflon. All ended up getting dried out and replaced. Current QA1 only a couple years in and had to put a drop of oil on one already.

The 1/2" rod ends on the new three piece sway bar use nylafiber instead of Teflon and require no lube. We'll see how that goes long term.

So rubber, poly, teflon, or delrin, all personal choices and subject to end result wanted.
But I do understand about keeping the wife happy. For mine it wasn't as much to do with the ride quality, it was the clutch and shifting that bothered her. It wasn't until the McLeod RST went in that things got a little better.
Bob

Didn't get as much as I hoped done but there was progress. I measured atleast 3000 times and cut once. Once I put the pucks in, slide the bar through and put the axle flanges on I was within 1/32" of my outside flange to outside flange measurement (pictured), I'll take it. I measured the axle tubes and they came in at .155" thick (pictured).

From reading it seems the order you go in when welding the rearend is tubes to center section, brackets, then axle flanges. So I went ahead and welded the tubes to the center (picture), I didn't do a huge fillet weld as I was trying not to load it up with heat, I am happy with end result.

Thems some nice welds. Make sure you dig out the slag and crap from the plug welds and seal them up with some weld. Seen more than a few rears seep lube there.
Is there two plugs front, one rear per side? 8.5 is that .
Keep plugging away, soon time to order a drive shaft.

Bob

Yes, 3 plug welds every 1/3. Not sure what to do about plugs, they are hard as hell put that was just me pecking around with a hammer. I'll do some investigating on it.

Didn't get as much done as I hoped this weekend. I'm trying to time it where I'm not down more than 3-4 days between pulling 7.5 rearend, mocking up new rearend, and reinstall 7.5 rearend. This time of year I'm out in the car pretty much all weekend and don't want to cut into it much.

Plug welds on the GM rears I've seen will be oil wet from seeping. tack a pick and hammer and tap on the welds to see if there is slag. from welding. Maybe Ford had the better idea and didn't have seeping.
Bob

Yeah that does look real nice.

Thank you!

Does anyone have opinions on gears to use? From reading around it seems like Motive might be good. People say yukon were good but has went downhill on quality last couple of years. I'm sticking with the 3.73 gear size but just wondering if anyone has recent opinions on manufacturer. I don't care to spend a little extra just too have good quality and no noise.

Spend the money to get whatever you choose REM polished is my only advice. I'm not sure what gears Gearfx used in my 3rd member but they were REM polished and broke in on a dyno and they are whisper quiet.

I put Nitro gears in my 2021 Colorado and even though they were supposedly REM polished as well, they are NOT whisper quiet...

Setup can make the biggest difference in noise, are you going to set them up or have a shop do it?

A buddy that worked on a lot of mustangs swore by the Ford Racing gears. Now, that’s been many years ago and things do change.

However, I did a quick google search and based on some of the reviews on Amazon telling how quite they are, they might be worth a look. Although you’re going to find complaints about any gear set if they’re not installed properly.

Anyway, they still Appear to be made at Ford’s Sterling Axle Plant. They also seem reasonably priced compared to the “aftermarket” gear sets.

Thank you for the REM tip Lance. I actually never had heard of rem polish until your thread but had forgotten until you just now brought it up.

I'm going to do all the setup myself, that way if it's wrong I have no one to blame but myself and i like doing that stuff and learning. I saved and labeled all the carrier and pinion shims that came from it so that should give me a decent point to start at. I have everything needed except pinion depth gauge and I might have a lead on someone that would probably let me borrow it but not sure. If not I think I can get through it.


I will say that the Ford guys swear by the Ford gears even today from what ive seen on forums, they also love the 03-04 cobra Ford Racing 31 spline traction lok with carbon fiber clutch disc, they throw in an extra disc. What's amazing to me is the cost and that's probably one reason they love it. Here is the diff, gears, and install kit all FRPP from Yates Performance for $490 and I've thought about it. track lok link

The truetrac alone is $700 which is what I plan to use but for what I use the car for the above is tempting and plenty of guys racing with over 600 h.p. on slicks in a manual with the traction lock.

Any other opinions on gears I would like to hear.

The Ford Racing gears are identical to the factory gears except for the warranty on the part (the engineering numbers from a stock replacement to the Ford Racing ring and pinion gear set are the same). The warranty for the Ford gears is two years unlimited milage,but don't remember of the top of my head what the warranty is for the racing gear set.. We tell customers who want a different rear end gear to look into buying the Ford Racing gears due to the cost and have never had a issue with noise or anything as long as it's set up right. Ford updated the clutch packs and the friction modifier a while ago. The old friction modifier really smelled bad but worked great. We used to play a joke where we would put the empty bottle and hide it in the service writers desk or inside their computer and see how long it takes them to find it. The new modifier (xl-3 is the Ford part number) doesn't seem to work as well. We had some customers come back after 30000 or so miles with a shutter when turning so we put two bottles in every axle now and don't have a issue.

Thanks for input Chris, I'm glad to see someone with your experience on the Ford side reply. Not sure which way I'm going to go but what's your thoughts on the 31 spline traction lock reliability with the weight of a monte 3600lbs, a 450 h.p 490 ft/lbs 383, and a tkx 5 speed for a street car on street tires with a few spirited takeoffs from time to time? What do you think of the frpp traction lock overall?

+1 for the FRPP gears. I have a bunch of Ford friends and two who used to own what was essentially a ford shop. They EXCLUSIVELY use Ford Racing gears in rear ends they built. They had noise with every other aftermarket gear.

As for the Ford clutch type Posi.. my advice (and their advice would be) is to get a Torsen T2R or an Eaton Detroit TrueTrac. The clutch packs just don't hold up for Autox/road racing/drifting. For my friends that drift, they would do 3-4 events and have an open diff, then just weld the spiders. You're right the cost is minimal, you cant swing a dead cat in a ford shop without hitting a 31 spline 8.8 Trac-lok diff. Heck, I might have one in my shop right now. I used a TrueTrac and LOVE it. You know the old addage, buy once cry once.

Thanks for the input Travis

Sorry for the long delay in the reply,I had a busy weekend! The Ford clutch packs in your rear axle would be great for a street car. If you have plans for a race car then you might want to go another route. I looked back at our shop manuals and for a 2023 Mustang you can still get clutch packs like what's in your axle unless it's the Torsen axle. Now for a 2013 Mustang there was no option for the Torsen axle ,so any Mustang would use the same factory setup that's in your axle now (other that the solid axle). The GT 500 was rated at 662 hp that year and we just don't have many problems with the factory setup plus it's very quiet. It seems most clutch packs I replace was because someone changed the fluid and didn't put any friction additive in with the fluid. My 2018 F150 has a electronic rear locking axle and I wish it still had a axle with the old clutch packs! If I was building this axle for my car I'd use the factory setup and not think twice about it. When the Indiana state police used the Crown Vic we worked on a lot of their cars because a post is nearby. Those cars got the crap beat out of them but the axles held up well.

I also remember around 2000 Ford started to use the carbon fiber clutches and we has some shutter issues so they updated the clutches again and we don't have any issues. If you're going to use the factory setup be sure to get the latest clutch packs for the axle.

Thank you for your valued input. The crown vic rear was a peg leg and 28 spline, no matter what I will be going 31 spline so either way truetrac or traction lok I will be getting a new differential. If I was to get the traction lok if would be this one which is a frpp. It is 31 spline with carbon fiber clutch disc.

https://lmr.com/item/M4204F318C/Mus...ferential-With-Carbon-Fiber-Clutch-Disks

The gear kit I would get is something like this

https://lmr.com/item/LRS-4209FRB-K/Mustang-88-373-Ratio-Rear-End-Gear-Kit

Here is what it says comes in the frpp 3.73 install kit
(1) Ford Performance Parts 3.73:1 gearset
(1) Outer 2012 GT500 Style Pinion Bearing & Race
(1) Inner 2012 GT500 Style Pinion Bearing & Race
(1) Carrier Shim Set
(1) Pinion Shim Set
(2) Carrier Bearings with Races
(1) Pinion Seal
(10) Ring Gear Bolts
(2) Crush Sleeve
(2) Pinion Nut
(1) Tube Gear Marking Compound
(1) Cover Gasket
(1) Bottle of Motorcraft Friction Modifier
(2) Bottles of Royal Purple 75W140 gear oil

Still undecided but have plenty of time to think it through and what I want.

Been putting in quite a few hours at work so not had much time to work on the car. Last night I took a couple of hours and got the car in the air with the frame level side to side and the axle level side to side. I took a few measurements and recorded them but just mainly getting everything lined up. I'm hoping to finish with all my measurements Wednesday evening and pull the old rear. Thursday get the 8.8 in, measured, and brackets welded then Friday reinstall old rear and bleed brakes so it's ready to go for the weekend. That's the plan but we all know how that goes.

Two PITAs when pulling the old rear.
One is the flex line. You can remove the flex line at the Tee on the housing and just let it drain all the old fluid out of the master cyl. This may be a problem when you refill the master and want to get the air out of the master and lines when reinstalling the rear. What i do,did, is make a fitting to cap the female of the flex line and avoid all that re-bleeding the air from the entire rear system. Fortunately i have a GM Tee that is used on the rear housing to connect the three brake line points. Two 3/16" line nuts and a short section of tubing crushed to close off the lines is used on the outputs of the Tee.
https://www.inlinetube.com/products/ts01

The other PITA is the E-brake cables. When I remove the rear I remove the entire brake assembles and them remove the e-brake cables from the backing plates. The cable that runs over to the right side brake is the PITA to get out of you want to remove it with the rear. I found it easiest to back off the E-brake adjuster on the driver's side and then remove the cable from the backing plates. The cables have three tabs that fix them to the backing plates. I use a piece of alum tubing with the correct ID, slide it over the end of the cable and use the tubing ID to collapse the three tabs, the cable will release and slide right out of the backing plate.
Reinstalling the cables is just a matter of snapping them back in the backing plates.

Just did all that yesterday. My rear is sitting on a working bench for a back to 3.73 gear change.


Being you are going to be doing the rear swap a few times, by yourself, make a cradle to support the rear from falling off the floor jack. I have a helper to get mine in and out. We are both old and as we know it's always a question of balance at our age. When we go to see doctors they always ask if we fell lately. The answer is always, NO. Even if we did have the rear almost slid off the jack.
Bob

Bob, I hope it works out but my plan is just undo the 2 hard lines from the t and put a line clamp on the softline to keep it from draining the MC. I might have some caps with squeezed hard line I'll just have to see if they are the right size.

Didn't really think about the e brake cables I just figured they would be no big deal but glad you gave me a heads up. Also thanks for the reminder on being careful with the rearend as I'm always working by myself it's a challenge from time to time but if something goes wrong it's just mine and the dogs fault but he really doesn't care.

Sorry for whatever reason I thought you had a newer axle that had the 31 spline already installed and in that case I'd just replace the clutch packs with the latest part. I went back and on page 1 you said it's from a 97 and if it's a open rear axle, you'll need a new carrier anyways. I think the complete Ford differential is the way to go. The first link from LMR looks like it's just the factory style differential. You shouldn't have any problems with that for what you're going to use the car for.

I was able to get the rear out and do some measurements on the 10 bolt and 8.8. It is 5-5 /16" from the centerline of the rearend to the centerline of the bushings (ear height) on the 10 bolt, Bob came up with 5-1/4". On the 8.8 the same measurement was 5-1/2" so the ears are a tad higher. This second picture you will notice the black dots over the dead center of the bushing that's how I measured ear width difference. The ears on the 8.8 were 10" center to center, the 10 bolt was 8"









I measured the ear angle off the back housing and I got around 43° on the 8.8 and the 10 bolt.





Couple of other pictures comparing.

Sorry I'm coming late to the conversation. Was reading right at the beginning about control arm brackets, that you couldn't find them because of liability.

I found these on Amazon, says they are from Currie (Sorry if duplicate)

https://www.amazon.com/SUSPENSION-BRACKET-GREASABLE-INSTALLED-CHEVELLE/dp/B06XYTSJTF

And these uppers say they are for the 8.8 in a G body.
https://www.trickchassis.com/product/upper-8-8-arms/