My transfer case makes a loud high pitch grind/wine noise. it does it when decelerating and loss just about all engine braking power it also gets louder when you downshift. If I push on the gas alittle it will go away it doseit in 2wd or 4wd.

it is a 92 f-150 E4OD auto hubs and auto t-case.


what could be wrong with it

 

Check the fluid level. Mine made that same noise whenever it was low, and then it eventually grenaded. Chances are if it's low and you've driven it more than 10 miles, the plastics have melted off the shift fork and they are now probably digging into the hub.

 

i actually just filled and then it started this about 200 miles later.

it will go into 4x4 and 2wd like normal

 

It seems to me you should take dawn the T-Case to be inspected. It is not so difficult to disassembly, check/repair and then re-assembly/install again. The whole operation can take just 8 labor hours, includying some time going to local Parts shop.

Problem description sounds like some wear on it...

 

It sounds like you need to repair the transfer case as soon as possible before you lose all ability to drive it. How many miles is on the Vehicle?

 

165000 miles and we are going to take it down tomarrow

 

When you get it down, take all the bolts out from around the case and it will seperate in half. It will need a little convincing to get apart.

2 things to watch out for.

1. Inside the casing is a slot, and inside that slot is a magnet which holds the pickup tube for the pump in place as well. Make sure you don't lose that magnet. I did, however, but bought a magnet from the local hardware shop and JB welded it to the outside of the casing in that same general spot. I then filled the slot where that magnet would have went with some sylicone.

2. The snap rings which hold the 4WD gear and chain in place, and the 4wd hub in place on the mainshaft are a pain to get off. Before you even start, make sure you have a GOOD heavy duty set of snap ring pliers. You will also need a good set of duck-bill pliers, or C clip pliers. I bought mine from the local auto parts store and they worked fine.

With that being said, when you start pulling everything off the mainshaft, you will see a shift fork that slides a hub that engages between 2wd/4wd/Nuetral and 4wd Low. Inspect the hub and make sure there is no wear on the smooth surface that slides between the shift fork. Also make sure the plastics on the shift fork are in good shape. Make sure theres not a lot of excess slop between the hub and shift forks. Some is ok, but not a whole lot. It needs to move freely.

Those are basically the main componets that wear out in these transfer cases.

 

You will need a set of .09 tip external snap ring pliers. Check the inside of the case where the chain is at to see if there is any places the chain may be slapping the inside of the case. If there is you will need to replace the chain. You will also need to look at the shifter as it goes through the case to see if it has worn the case any. The planetary will need pulled to see if it is in operational condition or needs replaced due to the bearing surface inside the planetary set wearing out. Most of the time the bearings on the input and output shafts should be okay but it is ideal to check them to make sure that there is no excessive play in the bearing. One more thing, the oil pump needs pulled apart and cleaned. I assembled mine with some petroleum jelly (Vaseline) so that it would prime up quickly and not seize until the fluid flowed through. Clean everything really well and assemble with the black RTV as your case sealant.