jbrockwell

iTrader: (2)

Thought this may need to be put in advanced tech but I'll see what happens here.

Car is M6 making about 400whp. Daily driven, sees auto cross often and sometimes strip use.

Since a bolt in 9" or 12 bolt from moser, strange, etc. will run me from 2-3k, I decided to adapt an 8.8" from a mustang or explorer which would run me about $200 + fabrication materials.

I've heard of people using just the center section from the 8.8 and welding on the axle tubes from the stock 10bolt for ease of integration.

I see a few problems with this, but I also see problems with the alternative which is using the entire axle from a mustang/explorer.

My question for you guys is which way is the smarter way to do this? I have access to a full machine shop.

Here is what I've come up with for problems regarding each setup:




(A)---Using ENTIRE 8.8" rear end:

1. suspension/torque arm/panhard bar/ wont directly attach. mounts/brackets will need to be welded on.
2. brake dimensions/options will be from whatever the axle donor car is
3. wheel stud pattern will be from donor car (can get adapter to fit 5x4.75)
4. possibly might need different driveshaft (yoke adapter at a minimum)
5. abs/tcs wont work (fine with me as long as no lights come on that would void a PA inspection)


(B)---Using 8.8" center section and welding on 10bolt axle tubes

1. will suspension/sway bars/panhard/etc. line up correctly with new location
of brackets (distance will change from 8.8" center being wider than 10bolt)
2. axles themselves will be incorrect length (assuming you can use a 10bolt axle into a 8.8" center section and diff or use 8.8" axles in 10bolt axle tubes)
3. possibly might need different driveshaft (yoke adapter at a minimum)
4. abs/tcs wont work (fine with me as long as no lights come on that would void a PA inspection)


Solutions so far:

B-2: order custom axles that fit into an 8.8" diff, 10bolt tubes, and have a 4th gen lug pattern

B-1: cutting down 10bolt axle tubes to make suspension mounting brackets-etc all line up the correct distance from the center section. (same distances as stock 10 bolt)



Any input or ideas you guys have is extremely welcome and greatly appreciated. Also, if anyone has CAD files of these axles or even parts it would be extremely helpful.

hrcslam

The lights for the ABS can be tuned out.

I think the custom axles, weld on tq arm mount, and center section with the 10 bolt tubes would be the easiest. It seem to be the most common method too.

I am very interested in this set up. So can you please make a build thread with part numbers, merchant info, and prices along with your measurements and process (and lots of pics too) when you do decide to do this? Thanks!

jbrockwell

iTrader: (2)

Once I begin ordering things/pick up the axles I'll write up a build thread for sure.

Ill start as soon as I have a solid plan laid out so I spend as little time as possible correcting mistakes or figuring things out after the work begins.

hrcslam

Cool man thanks

hiltsy855

iTrader: (35)

Lots of 8.8 build threads out there. If you go with an Exploder 8.8 & custom axles you'll have the benefit of 31-spline rear vs. the 28-spline 10-bolt axles.

https://ls1tech.com/forums/gears-axl...-question.html

https://ls1tech.com/forums/gears-axl...ount-help.html

https://ls1tech.com/forums/gears-axl...-now-pics.html

https://ls1tech.com/forums/gears-axl...-brackets.html

jbrockwell

iTrader: (2)

Awesome man thanks

hrcslam

How much is that tq arm mount?

hiltsy855

iTrader: (35)

Regarding the driveshaft for the 8.8, the stock F-body driveshaft will work with a Precision 355 or equivalent universal joint. When you get the Exploder / Ranger rear make sure you grab the flange yoke, that's the 4-bolt yoke that bolts to the pinion flange.

jbrockwell

iTrader: (2)

That makes things that much easier, thanks. I also checked out your links and they were very helpful.

It looks like the plan is to use an 8.8 center section (posi/3.73), weld on 10 bolt axle tubes cut down to length so the suspension lines up properly, use the stock 10 bolt axle shafts (from what I've read are the same used in the 8.8 28 spline), fab a torque arm/mount, and use a yoke adapter to make the stock driveshaft fit.



So the few remaining questions:

1. Can anyone confirm that the 28 spline 8.8 axle shafts are the same as the 10 bolt 28 spine shafts?

2. Is the stock driveshaft a slip spline into the transmission output? If not and its a fixed flange than I would think there would be a length issue with the driveshaft being too long after installing the yoke adapter to fit the 8.8.

3. Material of the 8.8? I read another member could not weld a torque arm mount onto the center section of the 8.8 because of it being cast. I was under the impression the entire rear was steel - how else would the tubes be welded onto the center section?



Finally, once I begin purchasing the axles and starting to work on this, I'll write up a build thread, step by step instructions/measurements, a bill of materials and costs, and hopefully a detailed video as I have not been able to find one.

Thanks everyone for the input.

Pocket

iTrader: (22)

1) Yes, they slide right in and C-clips retain them just like the old 8.8 axles. Use a ranger or car axle for easy insertion of the Fbody tubes. I had to kiss the OD of the Fbody tubes with a grinder because they were ovaled slightly. Not hard

Key is axle to flange measurement. This ensures the bearing rides in the correct position and the seal does its job. Measure the 10 bolt before cutting the tubes off

2) Fbodys use a slip yoke. 4L60E and T56 both have a 27sp output shaft. The flat flange on the 8.8 isnt something you see on any GM car. Load the suspension and measure from the flange to the tip of the output shaft and tell a DS shop what you're doing. They will build one to suit

3) The differential is cast nodular iron. Welding to it requires pre-heating and a special filler rod. To do this properly, the entire diff must be completely disassembled and rebuilt after. IMHO, this kills the reasoning behind building a 8.8. Cost effective tough axle. Rebuilding the axle, fresh seals, setting up the gears, swapping gears, new diff, aftermarket axles etc, might as well buy an aftermarket axle and just bolt it in

The tubes are common mild steel so weld on them all you want. Im a fan of the "wing" style TA mount. Run something structural from the drivers tube approx 45* to the diff locating the mount. Then wrap steel straps around the snout of the diff, bolting to the pass side and going under the snout. The "wing" hold the up/down rotation of the axle while the straps keep it from moving L/R

An off the shelf alternative is the maxim motorsports TA which bolts on any 8.8 from below. That skips fooling with a hard mounted TA mount completely

JRENIGAR

iTrader: (37)

An off the shelf alternative is the maxim motorsports TA which bolts on any 8.8 from below. That skips fooling with a hard mounted TA mount completely

I thought about this style of mount for an 8.8 build but wasnt sure what all else was required to complete the install. Any ideas?

hiltsy855

iTrader: (35)

The MM unit is built for a Mustang.

JRENIGAR

iTrader: (37)

True, so Im sure it will bolt on the 8.8 rearend. I was curious if anyone had attached it to an Fbody as a way to both bypass the stock torque arm and keep from having to weld the bracket you make to the 8.8 rear.

hiltsy855

iTrader: (35)

The MM unit will bolt to some 8.8's, the ones that have the flanges on both sides of the pinion. Exploder 8.8's do not have the required flanges and I'm not sure all Mustang 8.8's have them either.

pdquick01

iTrader: (3)

What I did was use the 8.8 from a crown vic, its only 1/2 narrower than the ten bolt. I measured all my angles and such from mine, cut and rewelded onto 8.8. The backing plates will fit with a slight redrill so u can run fbody brakes. You won't have abs, and you can use adapters for lug pattern or redrill the axles for gm wheels, u lose 1/4 on each side but its not too noticeable, depending on the wheels.

pdquick01

iTrader: (3)

I'm also making a little over 400rwhp, m6 4:10 Ford racing gears, and I have beat on it purty good so far so good. The weak link is the 28 spline axles but I doubt it would break unless you ran slicks at the drag strip, the Ford limited slip carrier works great, leaves good even black marks. Lol

hiltsy855

iTrader: (35)

What did you do for a TA mount?

JRENIGAR

iTrader: (37)

Good work sir, can you post up some pics? If you had moser build some axles with an abs ring you would have harder axles and the abs option. 1/4 in on each side is nothing, what year crown vic did you use? The police interceptor cars have a watts link on them. That gives an option for better handling instead of the panhard crap GM put on fbody's.

jbrockwell

iTrader: (2)

Do you have any pictures or diagrams of this? Thanks.

I'm still searching for a 10-bolt and an 8.8 to buy so I'm currently designing two different possible ideas for a TA.

One is essentially a sleeve/bracket that will weld onto an axle tube with bolt holes to attach a TA to. My concern with this is that it will cause the welded tubes to separate.

The other idea is some bracket with pivot point that bolts over the diff cover using the existing bolt holes. When a load is applied, it will not pry in the direction that would pull the diff cover off creating a leak.

Once I finish the design I'll post up a pic.

Pocket

iTrader: (22)

The tubes wont separate. Weld them to the diff if it worries you

Heres a ranger 28sp 8.8 with Fbody axle tubes and stock Fbody axles. I later updated the design from a pair of tubes to a solid piece of angle


31sp explorer unit using two drivers side explorer axles. Pass tube extended via internal sleeve. 4"x5/16" angle from drivers tube for TA mount


Sleeve. 10 bolt mounts were cut off a junk housing and welded on the 8.8. Will fabricate the brackets from scratch the next time. That sucked