I went off roading about three days ago


truck was fine until i power washed it real well.

My real diff has seemed to develop a slip when i hit the gas it feels like the tires spin half a rotation. It is kinda a soft squeal noise almost. There is no grinding of any kind

I checked the fluid today and when I took the filler plug out fluid started to run out of the diff not only did I think it was supposed to be below the filler anyways the fluid was really more thin then my motor oil. It looked diluted almost a light brown. The fluid also had a slight burnt smell.

I plan to change the rear end fluid tomorrow when I get home from school. DO you think this may help my slip?

 

Well all signs seem to point to what you were probably already thinking, but I wouldn't think water would be able to work it's way into the differential that easily. I guess you don't have a choice but to try to change the fluid and see if that helps...

 

Did you drive through any deep water? If so you may have sucked some in through the breather. Also, have you ever replaced the fluid? Have you checked the front diff to make sure it doesn't have a problem also?

 

Oh yea, they'll suck in water - been there done that - 2000 miles later, she blew and was full of swamp water.. My breather was even tied up on the frame rail and I wasn't that deep - at-least I didn't think I was.

 

It wasn't that deep but I think Ill change the fluid today its been about 100 miles do you think that may solve my issue?

 

Don't know if it will help or not. I would do that first though before I would start looking for a new rear or clutch packs. If you have limited slip, don't forget the friction modifier. Also Ford now specs 75w140 for the rear diff now. 75w90 for the front. I would change both. Also check and make sure that the breather tube is not hanging down that would allow it to suck in water.

 

i looked around last night and could not find anything on the axle that looked like a breather tube.

 

I'm not sure on your model - I don't think it's on the pig/third member housing. I believe it's on the axle now.

 

ok ill check its a 97

it must have had water in it because isnt full 3/4 inch below the filler hole.

When I checked it it looked a lot like motor oil

 

# 23 = Breather/vent hose -



You have the 9.75 or 8.8 ?

I have both here.

 

Looks like it's here, but I thought that was the ABS valve on these axles. ??



What's your take on this Kingfish? My 90 model had one the pig.

 

I can not recall right now i am sitting in school. I have a 5.4l and a limited slip diff I know its the larger tranny and axle


come to think of it it has to be the 9.75 ill check the tag tonight

 

Here's the list that goes with the diagram in case someone wants it -


Item Part Number Description

1 — Rear axle identification tag (part of 4002)
2 4346 Differential housing cover bolt
3 4033 Differential housing cover
4 4241 Differential pinion shaft lock bolt
5 4N237 U-washer
6 4230 Differential pinion thrust washer
7 4215 Differential pinion gear
8 4211 Differential pinion shaft
9 4236 Differential side gear
10 4228 Differential side gear thrust washer
11 4067 Differential bearing shim
12 4222 Differential bearing cup
13 4221 Differential bearing
14 4216 Differential ring gear bolt
15 4204 Differential case
16 4B409 Anti-lock speed sensor ring
17 4209 Ring gear and pinion
18 4663 Drive pinion bearing adjustment shim
19 4630 Pinion bearing — (inner)
20 4628 Inner axle pinion bearing cup
21 — Bearing cap and bolt
(part of 4010)
22 9E731 RABS sensor
23 4A001 Vent hose
24 4022 Rear axle housing vent
25 — Brake junction block
(part of 4022)
26 4010 Rear axle housing
27 390943-S100 Filler plug
28 4616 Outer pinion bearing cup
29 4662 Drive pinion collapsible spacer
30 4621 Pinion bearing — (outer)
31 4670 Rear axle drive pinion shaft oil slinger
32 4676 Rear axle drive pinion seal
33 4851 Pinion flange
34 389546-S100 Pinion nut
35 1225 Rear wheel bearing
36 1177 Inner wheel bearing oil seal
37 1107 Wheel stud
38 4234 Axle shaft
39 34449-S312 Brake backing plate nut
40 2209 Brake assy
41 2248 Brake backing plate bolt
42 — Retainer clip (part of 4001)
43 4947 Differential clutch pack
44 — Steel plate (part of 4947)
45 — Friction plate (part of 4947)
46 — Shim (part of 4947)
47 — Belleville spring
(part of 4947)
48 — Thrust face of the differential case (part of 4204)
49 2C026 Brake disc (Lightning)
50 1107 Wheel stud (Lightning)
51 4234 Axle shaft (Lightning)
52 34989-S427 Nut (Lightning)
53 2C220 Rear wheel disc brake adapter (Lightning)
54 391718-S426 Bolt (Lightning)

 

Yea, it's the 9.75. - You have the same set up as I do.

 

thanks for all the help I am going to tackle this when I get home it just started and there is no grinding hopefully its the fluid. It did look way to high and was super thin