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Old 10-29-2005, 11:22 AM   #1
shelby987
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reverse issues

ok, so I went to backup the other day, and the rear seems to want to hop ALOT while in reverse......i mean, feathering the clutch out nice and smooth, right RPM's.....and it just wants to shake the truck apart.....any input?
It's a 3 on the tree setup with a 250.....not sure of the specific transmission, but I know on flat ground, I don't have this problem....slight to deep grades....I am screwed....thankfully all I had infront of me was a 6" curb....rather than backup all the way, I just ran over it!
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Old 10-29-2005, 12:10 PM   #2
Cat Fuzz
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Re: reverse issues

Sounds like the clutch. Give it a little more gas while letting out the clutch. I used to drive big trucks for a living and sometimes I'd space and let the clutch out to slow or with too little throttle and the truck would shake like crazy.
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Old 10-29-2005, 12:20 PM   #3
jhow66
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Re: reverse issues

Time to change out the clutch--not enough spring pressure in the disk or pressure plate. ( buy a NEW one--4 out of 5 rebuilt ones will do the same thing).
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Old 10-29-2005, 12:35 PM   #4
shelby987
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Re: reverse issues

anyway to test the clutch before I signup for a clutch replacement? Is this only going to be a problem in reverse.....or will I shortly see problems in forward gears also?
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Old 10-29-2005, 01:31 PM   #5
Robert1970C20rstbukt
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Re: reverse issues

I'd fix it ASAP. My uncle had an old 70's furd F100 with a 4 speed that did the same thing when you took off in 1st. He'd let the clutch out slow and the whole truck would shake. Turned out to be a warped pressure plate.
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Old 10-29-2005, 11:20 PM   #6
jhow66
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Re: reverse issues

Make sure you have some freeplay (clutch pedal moves a little before it has any resistance).
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Last edited by jhow66; 10-29-2005 at 11:21 PM.
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Old 10-29-2005, 11:25 PM   #7
jimfulco
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Re: reverse issues

Is it wheel hop or is it the clutch chattering because of a bad disc or bad motor mounts. Mine used to chatter so bad in low or reverse that the hood would bang like a big old gong. New motor mounts (front & rear) tamed it down pretty well.
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Old 10-29-2005, 11:44 PM   #8
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Re: reverse issues

if it is chatter, there could be a few reasons including a warped pressure plate, warped flywheel, oil on the fly wheel from a junk rear main seal, weak spring pressure... even the fubared motor mounts.
Either way, it will get worse, it will start doing it on forward gear take off, and it is not good for the Zbar and linkages. (let alone the trans bearings and mainshaft...and to a lesser extent...the shock goes up the crank shaft too.
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Old 10-30-2005, 12:31 AM   #9
rwgregory
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Re: reverse issues

As all of the above have said, "your clutch is toast", (and we don't mean the
toast of the town...). It WILL get worse. Probably far from home, at night, on
a holiday. Tear it down & replace EVERYTHING with new, not rebuilt parts. Put
in a fresh throwout bearing, pilot bushing, clutch disc and pressure plate.
Remove the flywheel and have any good machine shop surface it. If you do all
of the labor yourself, you will probably spend about $300.00. Also, with the
flywheel removed you can inspect the rear main and pan seals and make sure
your clutch slippage is not "oil-assisted". Good luck!!!
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Old 10-30-2005, 07:18 PM   #10
powell72
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Re: reverse issues

My wife's truck did the same thing, put a new clutch in when we did the motor, and it went away.
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Old 10-31-2005, 07:52 AM   #11
Blazer1970
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Re: reverse issues

Check for a bad motor mount before you start tearing apart the clutch.
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