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Jimmy's clunking again...

Lil Jimmy ('91 T-15, 4.3L TBI, 4x4) just isn't feeling well.

Here's exactly what it does. I back out of the garage straight into the driveway and it may pop/clunk once over the fifteen foot journey after it starts rolling. I continue backing out (slowly) while cranking to the right and it'll pop twice more during the turn. If I go further backwards it's fine. I put it in OD and straighten out the wheel and sure enough it pops maybe ten feet down the road, usually followed by two more within the next thirty feet or so. After that it's fine for the 25km trip to work, not a single clunk (aside from a damaged exhaust).

Here's what has me puzzled. When I eventually stop and leave it for a while, if I take off in the same direction I parked it in it appears to be fine. I can put it int neutral at a light and let off the brakes just to relieve all tension in the driveline, and again, it's nice and quiet taking off again. It only seems to happen while switching from forward to reverse, far worse while turning, regardless of my spiritfullness with the accelerator. It sounds and feels exactly like a clunking CV joint (they're fine), and it is felt through the floor under my left foot. Nothing is felt through the steering wheel, and the only thing banging around over bumps is the exhaust (definitely a different sound).

The torsion bar mounts are fine, as are both half shafts, the upper ball joints, the lower ball joint on that side (I'll try to get around to installing the other one tomorrow) the idler arm, and the hub assemblies. The pitman arm and the tie-rod ends don't show any unusual play, and the control arms won't rock back and forth at all by hand so I assume the bushings are decent.

All I can guess is a worn but still tight to the touch U-joint, but I'm grasping at straws at this point. Any suggestions? I'll check the tranny mount when I check the U-joints just for the hell of it.

Oh and as a side note, is there a special trick to replacing the lower ball joint? That damned thing took me three and a half hours to install the other night, and that was just one of them! I had hoped that it was as easy as the uppers but I had to pull the transaxle (again) and wrestle it around the LCA. I'm considering popping the upper joint as well when I tackle the other side. Surely there must be a better way...

Reply to
SBlackfoot
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Blackfoot,

Had a look at the body mounts lately?

Doc

Reply to
"Doc"

Actually two bolts are broken, the one behind each front wheel. I'm preparing for a body lift and the only two I've tried so far broke right at the bolt head. The shanks are still rusted solid.

Now I was sure that the clunking started before I broke the first bolt, but now that you mention it...

At any rate, I just bought a hole saw so I can access the broken bolts from above. With any luck I'll have new bolts in there tonight.

Reply to
SBlackfoot

Keep us posted.

Considering replacing all my mounts with poly soon...

Reply to
burntkat IS AT comcast.net

I'll try... I'm still struggling with the first one. I drilled into the floor with a hole saw to gain acces to the top of the bolt and the nut, but the nut looks different on my '91 than other trucks I've read about. No piece of metal holding the nut down, a round nut rather than a square one, etc... I'd really hate to have to drill down through the whole bloody bolt.

Reply to
SBlackfoot

Update: I tried to remove the old body mount bolt by hammering an old 3/4" socket tightly onto the nut (definitely no hex on this thing) and going at it. A few minutes with a breaker bar and the result was a nice clean shiny ring around the nut and a slightly twisted 1/2"-3/8" drive adaptor (good thing it has a lifetime warranty), and the nut remaining in position defiantly. Oh Jimmy, why must everything be so hard?

My brother came up with a decent idea today (Yeah I was surprised too.). He suggested one of those new-ish "bolt-out" stripped bolt/nut extractors. They look pretty beefy and should grip onto pretty much anything, assuming I can get enough force against the nut. If they're strong enough I can even slap my impact gun on it and give'er heck. Any comments?

Reply to
SBlackfoot

if that thing has no hex on it, it may just be a nutsert.

Try the hutsert on the bottom- the shaft of the bolt. First, soak it down with PB Blaster, though.

Might want to try the blue wrench on it, too...

Reply to
burntkat IS AT comcast.net

Well all that's exposed on the bottom is around 1/8" of the shank. The head broke off and the nerf bars came loose (the nerf bars share that mount), so off it came. This was after being soaked repeatedly in penetrating oil. Not PB Blaster, but some kind of foaming stuff. It usually works great. There is still a block roughly 3" x 3" rusted to the bottom of the mount. If it will come loose with some (a lot of) force or not I'm not sure.

On the nut side all I see is a round nut around 3/4" tall sticking up in the hole I sawed, with the bolt threaded about half-way up. The nut won't turn so it must be welded to the body pretty solidly. I'm thinking that I'll have to whip out a nice big drill bit and drill down the middle of the nut and try to take out the end of the bolt, all the way to the sheet metal. Then hopefully pound the hell out of the rest of the bolt, and chisel off the nut. Then repeat 9x... Ugh...

Reply to
SBlackfoot

Gotta love Southern Ontario vehicles eh? I lived just North of TO (Aurora) for years and years and what a bloody mess all the damn salt makes on the undercarriage. NE Ohio is still pretty bad per way of salt on roads, but not nearly as bad as TO was.

Doc

Reply to
"Doc"

You know it. I'm just west of TO. Any car driven year-round looks like complete hell after a while. Even my T/A's undercarriage has it's share of holes. I'm afraid yearly oil sprays are about twelve years too late for lil Jimmy here too...

Reply to
SBlackfoot

Well guys, I think I have it figured out. (Sorry for the delay, we've had more than out share of family issues this year.)

I finally fixed that bloody body mount bolt and sure enough, Jimmy still clunks like a Ford. So, I climbed under and checked the tranny mount and I'm actually happy to report some movement. If I push and pull on the tranny I get a small clunking sound and some movement within the rubber. I guess that makes sense. I must've nuked it the last time I went four-wheeling, when I lost (literally) my middle skidplate, dented the hell out of the back one (which explains the mount damage), twisted the t-bar crossmember, dented my frame, and killed my y-pipe. I'm not going out again until Jimmy gets some ground clearance...

The new mount is currently on order and should be in on Friday, so with any luck Jimmy will once again be clunk-free by Monday. In the meantime, back to fighting with stupidly rusted body bolts...

Reply to
SBlackfoot

Well the tranny mount didn't work. Lil Jimmy still clunks when going from forward to reverse and vice-versa, while steering from one side to the other. Bloody hell...

Reply to
SBlackfoot

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