the truck: 1985 f-150 4x4

my rear diff is leaking. i want to replace the gaskets i guess. where do i start and any tips? its a 9" rear, so i guess just pull the axles and unbolt it, replace the seals and go about my merry way right? i also think it has some slack in it, i get a clunk when i get into gear a little hard, dont know if thats because of slack in the rear diff or tranny mounts... i just replaced the u joints

i want to swap out the front axle for a solid axle. i have the independent right now in front with coils springs and two shocks on each side. i guess a pre 80's front axle from a 250 will work? does it matter if its not a 9"? as long as the gear ratio is the same correct? i believe i have a 4.10 right now.

the transfer case i have now i hate. i believe i have to replace the mounts, but i hace no 4 low. so i want to snag one from a bronco. any issues with the swap or is it going to be a direct bolt on?

i feel a clunking over bumps and stuff under my feet on drivers side. could it be the case hitting the floor pan? replace mounts i guess? also i believe i messed up my hub lockers... should i replace with warn or OEM parts will do the trick? i need to replace the u-joints up front...how do i replace the axles to press them out? major issue or can be done in a little more time then it took me to do the rear axle?

TIA

 

it depends on where your rear diff leak is at. It can leak at the pinion seal, at the pinion housing, or at the entire diff seal. The first 2 wouldn't require you removing the axles. The last one does. And yes, just pull the axles shafts out, remove the driveshaft, all the nuts around the thing, then take it out. It is very heavy, be careful. You will need new copper washers to go under the bolts.

Tcase- depends on the model. If its the same model, no problem. It its different, you will likely have driveshaft length issues to deal with.

The front is not a 9", either a dana 44 or 60. Ratios must be close, like 4.09, 4.10 or 4.11. the axle from a F250 would be a leaf spring axle. It wont be a straight bolt in.

 

any possible way to convert a leaf spring front axle into a coil spring?

t-case...i think i have that covered then.

thanks for the help

 

oh, and the leak...hmm... looks like its coming from out the yoke. that can be replaced without removing the diff? also what gear oil would you use? fill plug is on the diff correct?

 

The front leaf straight axle can be swapped to accept coils. One of the off road companys on the net has the <> wedges you need to weld back on the axle for the radius arms.

If your looking for 8 lugs then the front D44 will be a leaf sprind axle. If you just buy a D44 from a F150/bronco then it will have the matching 5 lug pattern to match the 9 inch rear you have and it will be less work to swap and save cash by not having to buy the <> brackets. There is plenty of info on this type of swap just spend some time searching the net and you will find all you need.

The pinion seal on a 9 inch is not a straight forward unbolt and then bolt back on sort of thing. The pinion has to be set to the correct preload which sets the bearings to the drag. There is a crush sleeve on the pinion that helps set the preload when torqiung the piniuon nut down. if you get it to tight the bearings will fail in no time and if it's to loose the same thing will happen. A new crush sleeve should be installed when changing the seal. I have shall we say jerry rigged a few things in the past but it was not on a daily driver truck.

As for gear oil just good old 80-90 gear oil and if you have a trac loc then yoiu need the additive or buy the gear with the additive in it.