Thunk

[James Morse]

 

[97RangerXLT]

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I am jealous of how rust free your trucks underside is....

AJ

 

[lil_Blue_Ford]

I am jealous of how rust free your trucks underside is....

AJ

+1

 

[scotts90ranger]

Well, there's why it's an aftermarket driveline, it's one piece where it was two piece from the factory... unless you didn't take a pic of the middle chunk...

Put the transmission in neutral, engine off, parking brake on and grab the driveshaft, with a limited slip you will have some play back and forth (the amount will vary depending on gear ratio), it should only rotate a fraction of a rotation...

Yeah, mine all look about like that, aside from the '90, it's greasy and gross since the oil leak has been bad enough to get oil spots on the rear mud flaps...

 

[James Morse]

Didn't 4x4 Ranger have one piece rear driveshaft oem? I mean, there's the slip joint up front covered by boots, but the shaft itself I think was one piece, no reason for it to be two piece right?
I'll check shop manual, it should define what was on it new.

 

[97RangerXLT]

Didn't 4x4 Ranger have one piece rear driveshaft oem? I mean, there's the slip joint up front covered by boots, but the shaft itself I think was one piece, no reason for it to be two piece right?
I'll check shop manual, it should define what was on it new.

Not the 97. I think 98 and newer did, and it is a great swap for the older extended cabs. 97 and older had a two piece with a carrier bearing mounted to a crossmember between the two pieces. The front piece is only like 2 ft long tho

AJ

 

[James Morse]

Yeah, 2 pc. I don't see where the center bearing holder would have been attached but it must have had one.
What I have in there now is one long driveshaft approx. 3-1/2" o.d. and approx. 48" long. From the Fort Wayne guys.
3.73 8.8" with lsd

I found the diag for "Clunk" in the shop manuals. "Loud clunk in driveline when shifting from R to F" I assume that includes F to R.

"Possible source:"
High idle speed (not that, it idles about 650-700 warm) -- we covered that earlier, I thought maybe it was that, but it's not.
Loose engine mounts -don't think so
Loose or worn driveshaft components - I don't see any play in the driveshaft U-joints at all
Rear axle companion flange attaching nut below specification - I don't know what this is yet
Rear axle shafts or differential - maybe
Inoperative shocks absorbers or loose rear springs or suspension arms - I don't see anything loose or excessively worn bushings
Excessive backlash in axle, or transmission - the manual says "There is no effective way to check backlash on limited slip differentials." which I have.
Insufficient lubrication - don't know status (!)

Where is the place to check diff level, on top of the diff?
It looks hard to get to. I've been meaning to check diff levels and haven't done it, so I should eliminate that.

When I put the truck in N and parking brake on, I can turn the driveshaft maybe 1/8" to 1/4" something like that, not zero, but not huge. It's like this: I can turn it a bit, it has a little rotational play, but if you push harder to turn it you can hear and feel something move in the diff or axle and likewise if you go the other way. In other words it seems to reproduce it, taking into account I'm not turning it hard like the trans would.

I had my other half stand on both sides and did a bunch or R-F-R-F and she agrees it's coming from the left side, you hear it more there. If I just shift at a warm idle with no throttle, it's small but there. In my normal driving, I'm giving it some gas, so, you can hear it all the time.

Maybe it's normal but if not I need to keep chasing it.

 

[sgtsandman]

Yeah, 2 pc. I don't see where the center bearing holder would have been attached but it must have had one.
What I have in there now is one long driveshaft approx. 3-1/2" o.d. and approx. 48" long. From the Fort Wayne guys.
3.73 8.8" with lsd

I found the diag for "Clunk" in the shop manuals. "Loud clunk in driveline when shifting from R to F" I assume that includes F to R.

"Possible source:"
High idle speed (not that, it idles about 650-700 warm) -- we covered that earlier, I thought maybe it was that, but it's not.
Loose engine mounts -don't think so
Loose or worn driveshaft components - I don't see any play in the driveshaft U-joints at all
Rear axle companion flange attaching nut below specification - I don't know what this is yet
Rear axle shafts or differential - maybe
Inoperative shocks absorbers or loose rear springs or suspension arms - I don't see anything loose or excessively worn bushings
Excessive backlash in axle, or transmission - the manual says "There is no effective way to check backlash on limited slip differentials." which I have.
Insufficient lubrication - don't know status (!)

Where is the place to check diff level, on top of the diff?
It looks hard to get to. I've been meaning to check diff levels and haven't done it, so I should eliminate that.

When I put the truck in N and parking brake on, I can turn the driveshaft maybe 1/8" to 1/4" something like that, not zero, but not huge. It's like this: I can turn it a bit, it has a little rotational play, but if you push harder to turn it you can hear and feel something move in the diff or axle and likewise if you go the other way. In other words it seems to reproduce it, taking into account I'm not turning it hard like the trans would.

I had my other half stand on both sides and did a bunch or R-F-R-F and she agrees it's coming from the left side, you hear it more there. If I just shift at a warm idle with no throttle, it's small but there. In my normal driving, I'm giving it some gas, so, you can hear it all the time.

Maybe it's normal but if not I need to keep chasing it.

There is a pipe plug with a square socket in it on the front of the differential for filling and checking fluid level. You may need to dig and scrape the dirt out of the socket in order to get a 3/8" drive ratchet or extension into the socket correctly.

 

[James Morse]

I see rear diff fill plug it's not dirty or anything (yet, ha ha). Book says level should be 1/4" to 9/16" below the bottom of the fill hole.
Before I take out plug I thought I'd want some fluid on hand. Book says use Ford Part XY-90-QL. I'm seeing a lot of Ford axle lube but not that exact spec. Where do I get that?

Likewise front diff Part F1TZ-19580-A, I need that maybe.

There's the Ford spec also (besides the part#), so if I use a different Part, it should at least meet the spec, I'd think.

Maybe I should just check both and if they are not low then I could avoid cost, but it seems like I might want to have the fluids on hand. I would think unless there is a leak somewhere, it shouldn't lose fluid.

 

[sgtsandman]

80W-90 seems to be the standard for Rangers. You could go to the gear oil manufacturer’s web site and look up the specifications of what you are looking to use. They should list what specifications they meet for the different vehicle manufacturers.

As far as getting the level to spec, that is tough to do. Most fill it to the fill hole and insert the fill plug after the gear oil stops dripping out.

Gear oil stinks. If you want less stink, 75W-90 synthetic is acceptable.

 

[lil_Blue_Ford]

80-90 is the standard, it’s so common for Fords that I buy it by the 5-gal bucket. My F-150, because I’ve plowed with it and work it, I use 95-140. My green Ranger running the 5.0 I went 95-140 synthetic. It’s overkill, but I think it’s entirely acceptable for what I’m asking of those trucks.

 

[James Morse]

It stopped doing the thunk a while ago. I have to think something was just balky or sticky from non-use.
And of course I don't believe in things "fixing themselves" but you can have situations where maybe truck sat for a while with last owner and things just need to be used to free them up.

 

[ericbphoto]

It stopped doing the thunk a while ago. I have to think something was just balky or sticky from non-use.
And of course I don't believe in things "fixing themselves" but you can have situations where maybe truck sat for a while with last owner and things just need to be used to free them up.

Or it fell off and you need a new one. But you don’t know what it is that you need. If it’s important, you’ll find out.

 

[James Morse]

Yeah, I don't think anything fell off. I hardly put miles on it at all, pretty sure I would have noticed something falling off. I have to think it was just something sticky and with use lube got spread into it and it went away.
Certainly if I see/feel anything weird I'd investigate, but everything seems to be normal. I'll check again, but last time I even tried to make it clunk and it didn't. If you have something in the driveshaft that was sticky but got freed up it could, theoretically, cause the clunk. Just spitballing there I know.

 

[sgtsandman]

The slip joint on the drive shaft could have been binding and you broke it lose. Maybe.