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Hello all I've got a 1990 F150 and I want to see about upgrading to an LSD. I'm not sure where to start on this and all that. I'm guessing I could either replace essentially the whole rear axel, or I could replace the internals of the diff? I think I'd be willing to do either method. just don't know what's reasonable. I've looked around here a bit and haven't found much that's been super useful. I can get the info off the door jam that can be decoded into which rear diff it came with if that would be helpful. I can also go underneath it to try to find out.
What gear ratio does the truck have now and is it suitable for the powertrain in it? You could gain both a better gear and an LS diff with a whole axle swap... which really isn't much more work than installing another differential. But if the gearing is OK then there are quite a few diff options available, you could just install an OEM TrakLok clutch pack diff but a Detroit TrueTrak gear based diff doesn't have any parts to wear out.
I installed the Aussie Locker in my 8.8" and ran it for about 30k miles. Cheap, easy install, and great performance off-road: especially with both sway bars and stiff suspension. It's pretty clunky and loud, and ice in winter was...interesting. Eventually the drive line slack from it drove me to not trust it. I went back to open. It was clear upon removal that the locker was heavily worn.
Then a year later I regeared my axle to 4.10, and installed a Trutrac differential. At the same time I halved the coil spring rates and went to a progressive leaf pack, retained only the rear sway bar. With better suspension, it's now rare to lift a tire, so a full locker is much less important off-road. The differential is great, seamless power transfer and you'd never know it's there (quiet, no weird quirks, tight) until you need traction and realize it's definitely not open as you just keep moving. If you're not swapping to a whole new axle to get the clutch based limited slip, I definitely recommend the Trutrac.
I installed the Aussie Locker in my 8.8" and ran it for about 30k miles. Cheap, easy install, and great performance off-road: especially with both sway bars and stiff suspension. It's pretty clunky and loud, and ice in winter was...interesting. Eventually the drive line slack from it drove me to not trust it. I went back to open. It was clear upon removal that the locker was heavily worn.
Then a year later I regeared my axle to 4.10, and installed a Trutrac differential. At the same time I halved the coil spring rates and went to a progressive leaf pack, retained only the rear sway bar. With better suspension, it's now rare to lift a tire, so a full locker is much less important off-road. The differential is great, seamless power transfer and you'd never know it's there (quiet, no weird quirks, tight) until you need traction and realize it's definitely not open as you just keep moving. If you're not swapping to a whole new axle to get the clutch based limited slip, I definitely recommend the Trutrac.
Sounds like your carrier was out of spec or something was off, I have installed several lunchbox lockers and they have performed flawlesley and lasted thousands of miles.
Sounds like your carrier was out of spec or something was off, I have installed several lunchbox lockers and they have performed flawlesley and lasted thousands of miles.
Could be the carrier was worn. Install specs all checked out though, so idk? Seems like a great option for a budget trail rig to me. But if needing to replace the carrier to install a budget locker (due to wear), I'm going full case locker.
I should point out that mine never failed, maybe it has another 50k in it, it just seemed like it might soon, and that wasn't a gamble I was willing to take.
Could be the carrier was worn. Install specs all checked out though, so idk? Seems like a great option for a budget trail rig to me. But if needing to replace the carrier to install a budget locker (due to wear), I'm going full case locker.
I should point out that mine never failed, maybe it has another 50k in it, it just seemed like it might soon, and that wasn't a gamble I was willing to take.
I have a 2wd 8.8 in 3.08 ratio f150, I also need leaf springs(I never seen a bent leaf spring before… no rear or front sway bar. I need shocks and springs and want a LSD because my truck wants to spin on wet grass downhill you know the drill. I have a gravel driveway and it’s steep and it likes to make the right hand side not gravel unless I get a run start and be gentle
I have OK tires, at but falken just lower cost kind.
I have little need for winter driving but I do need it to be useable for that. It’s doable atm but it’s a little frightening because enough weight in the rear likes to make the front HT Understeer a bit and I realize I should have matching 4 but it does make the front less weighted a bunch soooo
best option? I want to re gear I hate having a engine that likes to make power low and power not being made low because it’s got a cruising on freeway gear. Then I want LSD. I Feel a Ford 8.8 is enough for my purposes but I do own 2 Ford 9 inch from older trucks (no way to put vss in right?) I want to retain RABS. I also want beefier springs because mine were weakest factory ones. Maybe keep a look for a spring/axle set? F250 of frame isn’t different width? 3.55 sound good idea? Truck doesn’t see huge miles but it’s road primary. No lift in my plans. Has overload bumpers from PO. I want to keep 15 but could swallow 16 but i would be limited to only a slightly taller rear tire and have no issue having asymmetric sizing front to rear because my current set is type asymmetrical
uou seem like you know what you are talking about
I’m told my inside of diff was ok looking for 120k snd I believe it was oe fluid. I noted it smelled fine and was green tint but dark
Last edited by AuroraGirl; Jul 1, 2021 at 12:34 AM.
I have a 2wd 8.8 in 3.08 ratio f150, I also need leaf springs(I never seen a bent leaf spring before… no rear or front sway bar. I need shocks and springs and want a LSD because my truck wants to spin on wet grass downhill you know the drill. I have a gravel driveway and it’s steep and it likes to make the right hand side not gravel unless I get a run start and be gentle
I have OK tires, at but falken just lower cost kind.
I have little need for winter driving but I do need it to be useable for that. It’s doable atm but it’s a little frightening because enough weight in the rear likes to make the front HT Understeer a bit and I realize I should have matching 4 but it does make the front less weighted a bunch soooo
best option? I want to re gear I hate having a engine that likes to make power low and power not being made low because it’s got a cruising on freeway gear. Then I want LSD. I Feel a Ford 8.8 is enough for my purposes but I do own 2 Ford 9 inch from older trucks (no way to put vss in right?) I want to retain RABS. I also want beefier springs because mine were weakest factory ones. Maybe keep a look for a spring/axle set? F250 of frame isn’t different width? 3.55 sound good idea? Truck doesn’t see huge miles but it’s road primary. No lift in my plans. Has overload bumpers from PO. I want to keep 15 but could swallow 16 but i would be limited to only a slightly taller rear tire and have no issue having asymmetric sizing front to rear because my current set is type asymmetrical
uou seem like you know what you are talking about
I’m told my inside of diff was ok looking for 120k snd I believe it was oe fluid. I noted it smelled fine and was green tint but dark
Going from a 3.08 to 3.55 isn't enough of a difference to be worth it, I would go for a 3.73 at least. Then either put a lunchbox locker in the carrier you have or go with a Detroit Truetrac if you want a limited slip.
Going from a 3.08 to 3.55 isn't enough of a difference to be worth it, I would go for a 3.73 at least. Then either put a lunchbox locker in the carrier you have or go with a Detroit Truetrac if you want a limited slip.
if I go to that ratio would I be wise to do something else like bump up the rear tire size a small bit even if it means another step in ratio to have more contact area(so I guess a bit wider too) but I’m sure that 15 inch doesn’t get Too much bigger before I need to look at 16s
I do have a bit of room as it stands to fit tire back there but if I get beefier springs I’m sure I could squeeze a tiny more
just to help the giant little fella, I was already planning on Auxiliary cooler for e4od but if I’m gonna be roaring down the freeway and things of that nature perhaps I would best to install an auxiliary cooler but with a pusher fan?at least help offset the heat shoving into the condenser I suppose lol
Maybe even a deeper pan with new filter if I have the clearance for it
Last edited by AuroraGirl; Jul 1, 2021 at 08:40 AM.
In general, 3.55 is about the tallest *useful* gear I'll ever consider in a pickup. But I don't ever buy a pickup thinking "Oh man, this thing is gonna get *great* mileage" It's not why I buy them.
The 3.55LS combo was common in 5.0 and 5.8 trucks at higher trim levels, if you find one of those at a scrap yard it's a direct bolt-in. The LS diff would need a rebuild/restack to provide any useful traction, even brand new these clutch pack diffs were setup quite loose but they are tunable with shims.
The 3.55LS combo was common in 5.0 and 5.8 trucks at higher trim levels, if you find one of those at a scrap yard it's a direct bolt-in. The LS diff would need a rebuild/restack to provide any useful traction, even brand new these clutch pack diffs were setup quite loose but they are tunable with shims.
This. I can't speak to all yards, but pulling the case yourself in most of the yards here is really inexpensive, and can be done with basic hand tools. Heck, at a few of the yards here, just pulling the whole Axle won't break the bank, when it's a common one like the 8.8.
This. I can't speak to all yards, but pulling the case yourself in most of the yards here is really inexpensive, and can be done with basic hand tools. Heck, at a few of the yards here, just pulling the whole Axle won't break the bank, when it's a common one like the 8.8.
no local pull yards for 2.5 hours any direction they all say insurance as the reason
we got a few that are reasonable but doubtful they got many but not something to ignore either
i would prob watch fb marketplace you can often see a obs for parts or repair usually with a blown small block(ha nerds), deer damage, or iron oxide and it’s sister 600 pound Patricia found the weakest link in either suspension or frame. Bucket seats for obs been popping up like mad.
With growing popularity it’s not uncommon to see axles and rollers or just part outs from guys making their own nice obs
if I got a roller I’d definitely shoot for a f150 with the stuff you guys say with a good passenger fender and maybe tailgate ..he’ll now that I think..spare tire hood downs and rear gas tank…filler neck… nicer wheels…interior bits to upgrade…if the rear frame is good I can make another trailer… if bed ok..I have axles and I’m sure shoehorning any old random *** leaf springs laying around would not be hard lol
i almost got a roller with a good high mileage 4.9 just no trans(well what was left of an aod) and just like mine but crustier for 500 but had no money 😭
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
