Truck Bouncing Question
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Cross-Country
Joined: Jul 2016
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From: Michigan
Truck Bouncing Question
I have a question and was hoping that someone might have some insight about it. I have an 1981 F150 and while going down the road while giving the engine gas it rides smoothly, however when you let off the gas and engine brake the truck it hops up and down. It's nothing too terrible but is definitely noticeable.
My first thought was that my rather old shocks were the problem and they weren't settling the axle rolling from the engine. Since they are rather old I'm buying new ones anyway, but was hoping someone else has possibly already seen and solved this. Any other ideas would be greatly appreciated.
My first thought was that my rather old shocks were the problem and they weren't settling the axle rolling from the engine. Since they are rather old I'm buying new ones anyway, but was hoping someone else has possibly already seen and solved this. Any other ideas would be greatly appreciated.
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Cross-Country
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From: Michigan
Universals
They seem good, I had to replace the rear seal going into the pumpkin and the seal coming out of the front of the transfer. While I was there I checked all four and everything seemed good, put new grease in them also.
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Bouncing is a lot more result than I would expect, but the splines in the slip joint on the drive shaft can certainly cause problems when you let off the gas. Not sure what type shaft you have, but mine has a splined coupling just back of the front u-joint and it was worn so badly you could push the shaft side-to-side a bit.
You really can't see the splines that are worn until you pull the drive shaft out, but I'd pull the shaft and check them as well as the u-joints.
You really can't see the splines that are worn until you pull the drive shaft out, but I'd pull the shaft and check them as well as the u-joints.
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Cross-Country
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From: Michigan
Is it usually the splines in the slip yolk or on the drive shaft or a combination? When I changed the seal I thought it had a little more play than it should. Not nearly as bad as what you were describing, mine was a small rotational play, not side to side.
I also checked the rear spring hanger bushings this morning. They checked out.
I also checked the rear spring hanger bushings this morning. They checked out.
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FTE Legend
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Both. Try moving it side-to-side while in the truck. But take it out of gear and put the parking brake on first as well as chock the wheels.
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Cross-Country
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From: Michigan
I have a 1978 truck out back with a shafted still in it, how many different type did they make and what are the odds it would fit?
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Cross-Country
Joined: Jul 2016
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From: Michigan
I'll have to check that out, seeing I just replaced the seal that may be it. Gunna be a little bit longer however. I need to replace all the brake parts in the drums, ball joints in the front and a upper shock mount in the back... Amazing what sitting 5 years does to them
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