ZachStack

so i have a 1997 f150...i put the rear end in this truck, i pulled it from my old truck and i do not know how many miles were on it when the guy put it in my old truck. when ever i let off the gas and let it coast...i hear a poping noise...i cannot figure out what it is, i replaced the u-joints in the rear drive shaft, and the trans and tcase are brand new. i am almost positive it is my rear end...but i was just wanting to hear what someone might think it could be. it is a 9.75 ls 3.55 rear end. anyone else had these problems? or anything like it?

2000fordf1504x4

The only problem I've ever had is having one lock up on me lol

bonnen

really that could be anything, maybe the bearings in it are going bad, mine was popping not too long ago, opened it up and the spider gears no longer had teeth on it, when it comes to rear ends, all i can say is good luck.

2000fordf1504x4

And Napier gears are exspensive

ZachStack

Well...that puts a dark cloud over my day. Lol. I need to take off the diff cover and look..but if you were gonna do a swap what rear end would you use? I want disk brakes on the back of mine.

Almighty

I would swap in a sterling 10.25 from an f250 and convert it to discs

ZachStack

thatd be nice, but i still want a 5 lug bolt pattern

Almighty

Alot of jeepers convert Dana 60s to 5 lug

A7X

A 9.75 from an 02+ FX4... 3.73 LS, disc brakes...

'97-'98 9.75 had smaller pinion bearings, smaller axle bearings and 12mm lug studs... They were thrifty and used the same bearings as the 8.8...

Your pop in the rear could be many things... From your ubolts being loose/stretched or a bad tranny mount to a bad pinion bearing...

Check ubolts, check leaf bushings and shackle eye bushings, all external parts etc...

I've seen the tranny xmember crack just under the mount where you can't see it until you pull the plate underneath, (2) 18mm bolts and take a peek... That'll make a knock when letting off the gas as well as a bad mount...

Raise the whole rear off the ground, grab the drive shaft and push up and down, feel for play in the pinion bearings...

Pull the drive shaft and lube the splined end on the slip yoke

Then pull the diff cover after you've checked everything else and take a looksee...

ZachStack

i am glad you answered this one. thank you for the advise. i will do that this weekend. it is getting worse...it pops when ever i let off the gas and continues poping until i come to a stop. i have been working for a month strait now and have 20 more days until my first day off. so hopefully i can get it checked out soon.