Need advise on a rear diff for a 8.8 prerunner???

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I am building a 2WD prerunner (2005 F150) that will be mostly street driven, but when I am in the desert I want to make sure I have a fully locked rear diff. I am really torn on which rear diff to go with. Prerunning is not like trail riding or rock climbing. Its lots of wheel spin and drifting. I am no rear end specialist and everyone has there opinions. I am almost dreading posting this but if anyone should know, they will be on RDC.
I will be running my factory 8.8 rear housing & 31 spline axles for now with 4.88 gear ratio with 37" tall tires. I don't know whether to run a Detroit locker or select-able locker like a Eaton E-locker? I have no experience with either. From what I gather the Detroit locker is noisy on the street with a lot of clicking and clunking as it engages and disengages. Not sure if I want that. I like the idea of a select-able locker, but I heard that the Eaton E-locker for the 8.8 is weak? I don't really want to go with the ARB, too many things could go wrong with loss of air. What do most of you run in your rear diff specifically in the Ford 8.8 prerunners or 7200's other than a spool? Any help will be appreciated. Thanks.
 

Zambo

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I had a detroit in my pre runner and although I didn't notice any bad clunking noises when driving on the street, I wasn't impressed with how it handled in the dirt at speed. When it locked and unlocked it made the truck wander, which at low speed isn't a big deal but not what you're looking for when going around turns or trying to stay in the groove at 60 or 80 mph.

BTW, I'd be wary of using a 31 spline axle with 37s.
 
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Yes, eventually I will go to a full floater 9" or something of that nature but until then I need to run the 8.8 with 31's. Has anyone used a select-able locker in there 8.8 pre-runner?
 

wolverine

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I have an E-locker in my 8.8 bronco and would not recommend it for prerunner use. If you are planning on eventually upgrading to a 9inch, I would run an Eaton posi or a stock Ford limited slip in your 8.8 to get you by.
 

wolverine

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A posi or 'limited slip' normally has clutches that cause both rear wheels to be driven. They alow slip when turning and will slip if you get in a situation where one wheel is off the ground. It is never really locked like a spool or locking differential, but I think they can work decent off road. I ran an Eaton Posi in my 31 spline 8.8 F150 prerunner rear for a few years and was happy with it, then put in a full floater 9inch w/ a Detroit locker.
 

cs_drums

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Just run a spool! There cheap, strong and sound cool when you go around corners. Haha I don't have experience with detroits but I hear they can be kind of squirrelly on the street with the locker engaging and disengaging around turns.
 

mfs

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If you want it to live leave it open diff or the limited slip you will easily break axles with it locked up. Don't land with the gas on.
 

Brokenbronco

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My experience with an 8.8. For years i have defended using an 8.8 in my fullsize bronco. On my current build, i installed a detroit, toms wicked axles, and gears. I thought i was good to go, until i bent the housing and damaged the axles, r&p out in pismo. For a light weight truck the 8.8 will probably survive, not so much on a fullsize truck. I'm currently building a 9" to replace it, and would reccomend the same to you, if you have the means.
 
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With all this info and talking with Nate at AZ Diff I am going with 4.88 gears, Detroit locker, Diff cover with carrier supports, & Top Trussed Rear housing. He was very helpful & reasonably priced. I will let you know how it turns out. Thanks.
 

mfs

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I would take a spool over a locker any day. A locker makes a truck handle funky and they are loud all bet you will not like it.
 

Tech Tim

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Go ARB Air Locker and have the best of both worlds, open for the street and a full spool on demand.
 
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