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Rear end swap help

Posted: Sun Aug 05, 2007 3:21 pm
by hotrodboyzmn
I know it is goofy but I built up my ranger and paid no attention to the stock 7.5 rearend yet, the time has come. What do you think I should use. I am running a 347 carb putting out 450 horse at the crank and 490 torque, 3 speed auto transmission with manual servos and a 3500 stall. Suspension has been lowered and no traction bars yet. I need a posi, what is the best option. New to forum thanks for your help.

Posted: Sun Aug 05, 2007 5:59 pm
by 87ranger
either get a direct bolt in ranger 8.8 or get an 8.8 out of an explorer and chop it, with the explorer rear you disc brakes, 31 spline axles, 3 1/4 axle tubes, posi, and 3.55-4.10 ratios, that 347 must be honkin pretty good to be makin 490 ftlbs at the crank, i broke three 7.5's with my 302 before i switched to the ranger 8.8, how is it that your rear has survived this long?

no traction

Posted: Sun Aug 05, 2007 8:43 pm
by hotrodboyzmn
I am running 17x10" american racing torque thrust 2 with bfg drag radials, but I don't have posi, it is a one wheel wonder and gets 0 traction I can roast the tire at 75 mph if I want, I am pretty sure that is why there is no damage being done. I don't really drive it hard because there is no point without getting traction. The 347 is pretty crazy, we have kept the recipe secret, our local dyno guy said its one of the best naturally aspirated 347's he has dynoed, I guess we just found a nice mix of parts and machineing. Thanks. What year would be a direct bolt? Do I get it aftermarket or junk yard.

Posted: Mon Aug 06, 2007 5:49 am
by 87ranger
any ranger that came with an 8.8 will work, all 4.0 ranger have them and some 3.0 4x4 do also, but they will be 1.5 inches wider than your 7.5 unless you get a 92 8.8, all 93+ are wider if im correct, thats why i found it easier to just chop an explorer rear

Posted: Mon Aug 06, 2007 6:54 am
by cgrey8
Yes, the 93 and newer Ranger rearends are 3" wider than the pre-93 8.8s. I looked for nearly a month to find a pre-93 8.8 rearend. I eventually found a yard with a couple of 93 and older Ranger 8.8s. What I settled on was a 93 limited slip 8.8 with 10" brakes and anti-sway bar. It bolted right into my 89 Ranger with no hiccups at all. It is wider than the 7.5" that was there, but it's not nearly enough to notice especially with me still running stock size tires. If anything, it just gives more room to put a wider rim with 1.5" more backspacing in.

The things to note about a 7.5" to 8.8" upgrade are:
  • Parking Brake Cables and brackets are different so get ALL of the bracketry and cabling from the donor. And even then, you may have to cable-clamp the assembly to the main cable that runs to the pedal since the nodules at the ends of the cables are usually different sizes
  • The yoke that goes on the companion flange of the 8.8" RE is larger so get the donor's rearend yoke off the driveshaft. You can reuse your 4 bolts to hold the yoke to the flange
  • Expect to replace the limited slip clutch pack. When I got my rear home, I found I could overcome the clutch friction with my hands. It took some muscle to do, but I could do it. If my hands could turn the hubs and make the clutches slip, the clutches must've been shot or the stock limited slip is a joke. Didn't matter it was getting replaced with a PowerTrax locker and it don't slip
  • Try to get a RE with 10" brakes. They are the ones with the smooth drums. The 9" drums have ribs
  • The stock anti-sway bar is not that beefy, but if you don't have one and can get it, it's worth having. You need the bar, the hangers, and the bolts that hold it to the frame. On the driver's side the gas tank is right in the way. You can usually push the tank towards the center of the truck enough to slip your hand and a wrench between the tank and the frame to bolt the hanger in
  • I suspect the yoke location between the 7.5" and 8.8" is a little different. Hopefully it won't be enough to require driveshaft mods, but I suspect you'll find the tranny yoke doesn't land in the same place it did prior to the conversion
  • The brake lines should bolt right in. No problems here.
However if you go with an Explorer RE, there are quite a few mods you'll have to perform. Off the top of my head, I know you'll have to cut off the shock mounts and re-weld them back to the tubes since the Explorer locates the shocks differently than the Ranger. There's also an issue with the brake lines. something about them doesn't work in the Explorer stock location (I can't remember details on them). The parking brake cables are not compatible with the Ranger's setup. But I suspect cable-clamps could overcome that. And it seems the hydraulic brake lines also had some complication (again, can't remember the details right now).

The Explorer does give you the stronger 31 spline axles as opposed to Ranger 8.8s all being 28 spline (excpet for the STX). Explorer REs also come with rear disc. That could be important if you are planning to run aftermarket rims that are very open and would otherwise expose a big ugly drum. Others have reported that the rear disc improved their braking. However the 10" rear drums have never been lacking for me. But then again, I don't do a lot of hauling. My point is, the Ranger RE bolts in and has very few issues related to getting it to work. But expect the Explorer rear install to be a job. It's quite doable and many have done it. But it's far from a bolt-in solution. Hope that helps.

As for the power your motor's putting out, depending on the RPMs you are hitting 450hp at, I'd expect you got some AFRs on the decks. I wouldn't begin to guess at an intake since I'm not familiar with carbed intakes at all. But I assume the secret formula is in a custom cam?

Posted: Mon Aug 06, 2007 3:34 pm
by 87ranger
the 93+ ranger rears are 1.5"s(3/4 per side) total longer than the earlier rears, its the explorer rear that is 3" (1.5 per side) wider, thus requiring the need for a chop job or custom rims

Posted: Mon Aug 06, 2007 4:03 pm
by Dave
I'm not sure if anyone is running an after market rear, think a couple might be using the 9" rear, several using the Explorer rear but most have used the stock Ranger 8.8. A stronger Ranger axle might be the F4X 4x4 that comes with the Torsen rear end and usually in 3.73 or 4.10 gears with the 31 spline axles. You're not that far away from GregR in Red Wing MN who visits here often, got a later model Ranger with a DOHC 4.6, check the member list. You've got one hell of a power house of different cars in you collection.
Dave - in Central Wisconsin

great

Posted: Mon Aug 06, 2007 4:06 pm
by hotrodboyzmn
Wow thank you so much for the in depth description. I will begin my hunt for an 8.8 tommorrow, I am going to post a new subject on transmission, I will post a few pics of my truck soon. I will keep you updated in the meantime if anyone has more info feel free to leave it. And yes AFR heads are being used and a high rise air gap edelbrock intake, aluminum flywheel, solid lifter with roller rockers, etc. in the 347.

Posted: Mon Aug 06, 2007 4:12 pm
by hotrodboyzmn
Dave,
Thank you I will check it out, your list is equally as strong, once you have power it is hard to go back. I am pretty excited about the new toy (ranger) though, I just hope I can work out my traction issues, maybe I will have to go full four link in the rear but I will start with the rearend and go from there. Thanks again guys, if you want to put any input in my transmission swap it is in another forum under transmission suggestions.

Posted: Mon Aug 06, 2007 4:25 pm
by cgrey8
87ranger wrote:the 93+ ranger rears are 1.5"s(3/4 per side) total longer than the earlier rears, its the explorer rear that is 3" (1.5 per side) wider, thus requiring the need for a chop job or custom rims
I'm afraid I have to disagree on this one. My 93 Ranger RE is 1.5" wider on each side (total of 3").

Here's pics of my 7.5" before I replaced it:
Image
Image

Here's a pic of the 8.8":
Image
Image

Notice the 7.5RE is 4" from the spring perch to the end. The 8.8RE is 5.5" to the spring perch...a difference of 1.5" per side.

Posted: Mon Aug 06, 2007 4:54 pm
by Dave
Chris,
Had to check the 2000, same as what you show with the '93' rear. A 8" rim with 5 1/2" back set centers the tire in my truck.
Dave

Posted: Mon Aug 06, 2007 5:16 pm
by cgrey8
Oh and for extra traction, I run James Duff traction bars along with the previously mentioned PowerTrax automatic locker. They do a pretty decent job. The truck doesn't do the bunny-hop like it used to. But I'm not running anything major under the hood like you are...all stock 97 Explorer motor, aftermarket T5 with altered (higher) gear ratio, 3.27 rear gears, and stock tires. If I dump the clutch in 1st (2.95 ratio instead of stock 3.35), it'll break the tires loose and keep'em broken. But they quickly catch traction in 2nd (1.94 vs stock T5's 1.99 ratio).

With 3.73s and a production T5, I feel like that'd be a different story...

Posted: Mon Aug 06, 2007 5:39 pm
by 87ranger
this is the info i used when chopping and using an origional ranger 8.8 and the tape measure agreed with the list of measurements, dont know what to say??


http://www.therangerstation.com/tech_library/Axles.html





Ranger 4.0 1990-1992 Width is same as other pre-93 axles, 28 spline
3.08 (4x2), 3.55, 3.73 and 4.10 (4x4) factory ratios
Either limited slip or open differential
10" drum brakes

Ranger 4.0
B4000 1993+
1994+ Width is same as other 93+ axles (1.5" wider than pre 93), 28 spline
Ratios and differential options as noted above
Ranger FX4 2002+ Width is same as other 93+ axles, 31 spline
4.10's and Torsen limited slip from factory
Explorer
Navajo 1990-1994 Width is 1.5" wider than 93+ Ranger, 3" wider than pre-93, 31 spline
Spring perches must be fabricated and welded on top
Stock spring perches can be used to lower the truck (like a flip kit)
Shock mounts must be fabricated and welded on
Very common to find ltd. Slip, usually 3.73 or 4.10 (4x4) gears

Explorer
Mountaineer 1995-2001 Same as above, also has rear discs

Posted: Mon Aug 06, 2007 5:49 pm
by 87ranger
try measuring drum to drum maybe there is a difference in axle flange/ brake backplate spacing between the 92 and earlier and the 93 and later, when i had my ranger 8.8 and a 7.5 and my recently purchased explorer rear, the ranger 8.8 was 1.5 wider than the 7.5 and the explorer was 3 inches wider

Posted: Mon Aug 06, 2007 5:59 pm
by cgrey8
I remember measuring between the perches and they were the same width between the 7.5 and 8.8. The fact that I bolted it right into my truck confirms that fact.

But what you say may be true that the width hub-to-hub may be different. I don't recall a great difference, but I don't think I ever took the drums off the 7.5" to notice any width difference between the axle hubs and the pipes between the two. My old 7.5" is still out at the old house. I don't go out there but maybe once a month just to clean the junk mail out of the box. I'll try to remember to get some more measurements & pics next time I'm out there. Then I'll have to jack the truck up and get the rear drums off and measure there too. So you may still be right.