Banging noises mystery

[JoeBWhite]

Hey all - I've seen some other posts asking about banging and knocking noises. Here's my situation: I have a 1961 D100 Town Panel, 318, four speed. The truck starts, shifts (with some grinding,) and runs but at 30+ mph there is a lot of loud banging noise coming from under the truck. Guy at the shop said it was the rear diff about to go. He wants nothing to do with it. Other posts make me wonder if the problem is something else. If it is the rear end, I'd welcome recommendations. I'm not an expert mechanic and don't have a lift. Specs on the axle - it's an 8 3/4 and the frame width is 38". Are there modern or easily available second hand axles that would fit?

Thanks Joe

[dodgeboykim]

Hey all - I've seen some other posts asking about banging and knocking noises. Here's my situation: I have a 1961 D100 Town Panel, 318, four speed. The truck starts, shifts (with some grinding,) and runs but at 30+ mph there is a lot of loud banging noise coming from under the truck. Guy at the shop said it was the rear diff about to go. He wants nothing to do with it. Other posts make me wonder if the problem is something else. If it is the rear end, I'd welcome recommendations. I'm not an expert mechanic and don't have a lift. Specs on the axle - it's an 8 3/4 and the frame width is 38". Are there modern or easily available second hand axles that would fit?

Thanks Joe

Dodge pick ups from 61 to 74 should bolt in, But use the non ( Nut at end of axle)keyed 8 3/4 axle ones from 64 ish to 74.
Someone else can probably add some insight .

[earlymopar]

Without being there to hear it for ourselves, it is somewhat difficult to say for sure but noises like that are most often from the rear-end. Replacing the 3rd member is a simple and not time-consuming job. You could remove yours and have it rebuilt or find a good new or used replacement. Look at the # on your 3rd member. If you like your current rear-end ratio, having the existing 3d member rebuilt is a good way to go. If you want to change the ratio or upgrade the model of the 3rd member to a new or stronger unit, this is a good opportunity to do the retrofit.

- EM

[soopernaut]

A 3rd member swap is not going to be so easy in a pre 1965 axle. The later versions do not fit due to thrust block differences and early versions are difficult to find.

[Jim100]

Is the 61 axle in a town wagon of a different width or different spring perch width? If not any axle right up to 93 would work wouldn't it?

[PwrWgnDrvr]

The only good thing about a pre 65 axle is if u cut it in half it qualifies as #1 heavy metal scrap.

[MadMC63]

Just put it on stands, put it in gear and listen.

[JoeBWhite]

Thanks for the info. Obviously I'm learning as I go here. What's the problem with pre 1965 rear end/axles? It sounds like if I can replace the whole assembly - diff, housing and axles - with a 1965 or newer I'd be better off?
Dodge pick ups from 61 to 74 should bolt in, But use the non ( Nut at end of axle)keyed 8 3/4 axle ones from 64 ish to 74.

[dodgeboykim]

Thanks for the info. Obviously I'm learning as I go here. What's the problem with pre 1965 rear end/axles? It sounds like if I can replace the whole assembly - diff, housing and axles - with a 1965 or newer I'd be better off?
Dodge pick ups from 61 to 74 should bolt in, But use the non ( Nut at end of axle)keyed 8 3/4 axle ones from 64 ish to 74.

Using the later rear axle assembly will ease maintenance concerns for one.

[PwrWgnDrvr]

The early axle is a totally different design. The axles are tapered, held in by nuts and require massive effort and pullers to get apart. The internal parts are different, harder to adjust and there is no parking brake. That's probably why the shop told u they wouldn't touch it.

[aqmet]

Working with a pre-65 axle is a little harder than the newer versions but if you have a good axle puller it can be done. I have ’64 Town Wagon and a ’64 Town Panel and have swapped out the center chunks with 65-newer chunks and done rear brakes jobs on both. Any year center chunk from a car or truck will work with your 61 axles, (but as already mentioned a pre-65 chunk will not work on a newer axle).

The link below provides a good reference on MOPAR 8-3/4 axles, and I prepared a tech article on removing tapered axles.

8-3/4 Guide
http://www.mymopar.com/Mopar8_75RearEndGuide.htm

Tapered axle removal –
viewtopic.php?f=33&t=26161

Like I mentioned the key is having good axle puller, I would suggest looking on eBay for an older one, the new ones made overseas just don’t look as strong, I was able to find an NOS military surplus puller for about $100.

Good Luck
Mike

[aqmet]

I just read what i posted and realized that 1964 trucks have tapered axles BUT have the the newer style center chunk and 63 and older axles can not use 64-newer chunks.
Mike

[soopernaut]

I just read what i posted and realized that 1964 trucks have tapered axles BUT have the the newer style center chunk and 63 and older axles can not use 64-newer chunks.
Mike

Is this true? Did you do this on yours? From the My Mopar site, it sounds like it is, but it could also be a mistake. That would make the 64 axle a one year only axle, which I've never seen mentioned anywhere else before.

[aqmet]

I did do this on both of my 64's. The '64 Town Wagon I switched from a 3.91 sure grip to a 2.94 open (not sure of the year of the donor) on the '64 Town Panel I switched from a 3.91 open to a 3.23 open from a 72 D100. They both have several thousand miles on them with no issues.
Mike

[randosteele]

Don't know if you figured this out yet, but I had the same symptoms on my 61 w100. It turned out to be the knock gear or Clunk gear in the NP 201. I pulled it apart and welded it up and problem solved.

[randosteele]

nevermind, I just noticed you have a d100...... not a problem with your transfer case:)

[builder]

on mine it was a worn yolk and i checked everything, i could not see the yolk was worn had to take the driveshaft to a driveline specialist an he rebuilt the whole thing , balanced and smooth as silk

[Silas]

As builder mentions, my first impression was a driveshaft spline problem. Driveshafts have a wonderful ability to amplify their problems. If you haven't located the issue yet, as someone posted earlier, I suggest you raise the rear end onto jack stands (after chalking it really well) then have a listen. Does any sound seem like it is coming from way back in the rear or could it be closer to the cab?

[JoeBWhite]

I'm back to say thank you. This project got sidelined during the winter, but it's spring and I am determined. Suggestions of where to find a 65-74 Dodge Truck axle - other than a junk yard? is there a company that sells replacements?