Howling/thumping noise while driving 97TJ

Hey folks, can anyone tell me what the problem might be? It's a '97 TJ,
4.0, Auto, no lift, 31" tires, no driveline mods. When i'm on the gas, at
just about any speed, it howls. When I let off the gas, it thumps. If I
feather the gas so that it's just at a sweet spot where it's not
accelerating or using the engine to brake it it completely quiet. It also
just before this started would make a banging sound when just starting or
stopping, like something was hitting the floorpan hard. I'm guessing either
one or more universals, or possibly something in the pumpkin. I'm leaning
more towards the pumpkin after writing all this and thinking about it along
the way.

Anyone have an experience like this that can help me out? If I have to
replace anything stock, what would be a better aftermarket upgrade choice as
well? IE, if it's a ring gear maybe a locker would be easy to do at the
same time. Stuff like that.

Thanks,

Shawn

Bad U-joint or tranny mount is my guess.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Endo wrote:
>
> Hey folks, can anyone tell me what the problem might be? It's a '97 TJ,
> 4.0, Auto, no lift, 31" tires, no driveline mods. When i'm on the gas, at
> just about any speed, it howls. When I let off the gas, it thumps. If I
> feather the gas so that it's just at a sweet spot where it's not
> accelerating or using the engine to brake it it completely quiet. It also
> just before this started would make a banging sound when just starting or
> stopping, like something was hitting the floorpan hard. I'm guessing either
> one or more universals, or possibly something in the pumpkin. I'm leaning
> more towards the pumpkin after writing all this and thinking about it along
> the way.
>
> Anyone have an experience like this that can help me out? If I have to
> replace anything stock, what would be a better aftermarket upgrade choice as
> well? IE, if it's a ring gear maybe a locker would be easy to do at the
> same time. Stuff like that.
>
> Thanks,
>
> Shawn

Hi Shawn,
Too many symptoms to guess. Howling is usually the ring an pinion
or bad rear axle bearing. a snapping sound are usually broken teeth
getting caught, between teeth. I'd get it up on a rack, and not drive
it, as it may lock up and leave you stranded in the middle of freeway
lanes.
God Bless America, ßill O|||||||O
http://www.billhughes.com/

Endo wrote:
>
> Hey folks, can anyone tell me what the problem might be? It's a '97 TJ,
> 4.0, Auto, no lift, 31" tires, no driveline mods. When i'm on the gas, at
> just about any speed, it howls. When I let off the gas, it thumps. If I
> feather the gas so that it's just at a sweet spot where it's not
> accelerating or using the engine to brake it it completely quiet. It also
> just before this started would make a banging sound when just starting or
> stopping, like something was hitting the floorpan hard. I'm guessing either
> one or more universals, or possibly something in the pumpkin. I'm leaning
> more towards the pumpkin after writing all this and thinking about it along
> the way.
>
> Anyone have an experience like this that can help me out? If I have to
> replace anything stock, what would be a better aftermarket upgrade choice as
> well? IE, if it's a ring gear maybe a locker would be easy to do at the
> same time. Stuff like that.
>
> Thanks,
>
> Shawn

Well you called it. It let loose on me this morning on the way to work.
Was just driving along at about 35Mph when it just sort of let go and
started making nasty grinding sounds. Ended up limping the rest of the way
in 4WD. This is going to be real fun to deal with now. I'm about to go
down to the garage and pull the diff cover and see how bad it looks. I
guess i'll go from there once I know for sure whats actually broke.

Shawn


"L.W. ("ßill") Hughes III" > wrote in message
...
> Hi Shawn,
> Too many symptoms to guess. Howling is usually the ring an pinion
> or bad rear axle bearing. a snapping sound are usually broken teeth
> getting caught, between teeth. I'd get it up on a rack, and not drive
> it, as it may lock up and leave you stranded in the middle of freeway
> lanes.
> God Bless America, ßill O|||||||O
> http://www.billhughes.com/
>
> Endo wrote:
>>
>> Hey folks, can anyone tell me what the problem might be? It's a '97 TJ,
>> 4.0, Auto, no lift, 31" tires, no driveline mods. When i'm on the gas,
>> at
>> just about any speed, it howls. When I let off the gas, it thumps. If I
>> feather the gas so that it's just at a sweet spot where it's not
>> accelerating or using the engine to brake it it completely quiet. It
>> also
>> just before this started would make a banging sound when just starting or
>> stopping, like something was hitting the floorpan hard. I'm guessing
>> either
>> one or more universals, or possibly something in the pumpkin. I'm
>> leaning
>> more towards the pumpkin after writing all this and thinking about it
>> along
>> the way.
>>
>> Anyone have an experience like this that can help me out? If I have to
>> replace anything stock, what would be a better aftermarket upgrade choice
>> as
>> well? IE, if it's a ring gear maybe a locker would be easy to do at the
>> same time. Stuff like that.
>>
>> Thanks,
>>
>> Shawn