76 CCDRW...Cummins noises

[76zimmer]

Stored at a friends place for the winter.
free of charge!
He used to charge $75/mo to pay for his shop (32x40) and after it was paid off he no longer takes in storage vehicles as he is starting to need the room for himself. He asked this year if I wanted to keep the Vette at his place again so I could get some work done over the winter.....its a good motivator!

I really should consider such an arrangement to help get myself more space as well!

 

[76zimmer]

pressure washed the chassis today, got rid of some dirt, grease and just gonna make it a bit easier to work on.
also went looking for the BOM on the rear D70HD. difficult to read after 40 years, but here is a thread on the two D70's, check it out and let me know what you think the BOM's are.
https://ck5.com/forums/threads/d70-...r-best-guess-on-these-stamped-numbers.324608/

some of today progress pics...some are just documenting the original frame markings

for easy access underneath....


A marking on the engine crossmember for ????


frame part number and date...Sept 30 1975




a couple of stripes signifying ????




D70 date casting



70HD...




that orange box to the right is where the BOM is stamped....part of it underneath the axle saddles, had to remove them to get the whole set of numbers.

 

[76zimmer]

Here are the BOM numbers from the D70HD and the D70U from the 98 Dodge:




this axle saddle broke at some point....the crack isn't fresh, but if anyone has a decent replacement I"m interested.

 

[kgblazerfive]

I was going to say, flip the U-bolts so they are on top, but then you sway bar wouldn't work.

 

[blazinzuk]

OK pics of the bed. Thought I would post em in the thread so you could reference back to them.





Stupid running boards probably caused this
Drivers side



Passenger side



Underneath pics





This is the support right at the rear of the bed

 

[blazinzuk]

Under the dually fenders










Rear corners





Bottom edge both sides





When I get all the crap out of the bed I will take pics of the floor for ya

 

[GWeakland620]

That's pretty clean!

 

[nvrenuf]

Cool! I see the diff cover has the rubber "Spicer" plug in the fill hole, pretty rare nowadays - don't let it go.

On your diff swap, I'm sure you can use the Dodge carrier but it might require some machine work on one journal and a fat shim/spacer on the other to move it over enough. Contact Carl jantz @ Jantz Engineering http://www.jantz4x4.com/jantz.php?p=home Carl has got it going on and can cross breed ANYTHING, super smart guy (went over my head quick but that's easy to do). I got my Jana 76 install kit from him.

nvm, I just saw n your other thread you got it figured out.

 

[76zimmer]

Cool! I see the diff cover has the rubber "Spicer" plug in the fill hole, pretty rare nowadays - don't let it go.

On your diff swap, I'm sure you can use the Dodge carrier but it might require some machine work on one journal and a fat shim/spacer on the other to move it over enough. Contact Carl jantz @ Jantz Engineering http://www.jantz4x4.com/jantz.php?p=home Carl has got it going on and can cross breed ANYTHING, super smart guy (went over my head quick but that's easy to do). I got my Jana 76 install kit from him.

nvm, I just saw n your other thread you got it figured out.

thats a good contact to have then thx
After reading the D70 thread on pirate it's a bit confusing to me still.
I really want to keep the HD housing and will stay with the drums as well as they are in pretty good shape and work good and can keep the braking system all stock.
can I use the D70U ring and pinion 3.54 ratio on the D70HD carrier(4.10)? Not sure what the break is there?
Still need to consider putting in a true track as well, which would replace the carrier I believe.

 

[76zimmer]

Eric I'll take a better look at the pics on a full screen later
Thx for posting them up and the more the better!

Tonight I stripped the frame of brakelines, fuel lines, unused brackets (exhaust hangers) etc. only the steering and front and rear suspension remain to keep it a roller
After pressure washing the dirt off its turned a nice deep rust color now!
The Frame Vin (somewhat different format from the body VIN) is easily read by the pass side engine mounting

 

[blazinzuk]

3.54 on the 4.10 carrier will work. It's 4.10 and down and then another split below 3.54.

Ever get both BOM # figured out.

On that bed lemme know if you want specific pics

 

[76zimmer]

3.54 on the 4.10 carrier will work. It's 4.10 and down and then another split below 3.54.

Ever get both BOM # figured out.

On that bed lemme know if you want specific pics

The BOM's:

The Dana website only went back to 1979, but the BOM was the same as my 76....

GM Model 70/267 REAR 1979 - C-30 DUAL WHEEL - 70HD - 4.10 standard diff

Bill of Material 603704-1



CHRY Model 70/267 REAR 1998 - D2500 W/ABS - 3.54 standard diff.

Bill of Material 606094-1

 

[76zimmer]

3.54 on the 4.10 carrier will work. It's 4.10 and down and then another split below 3.54.

Ever get both BOM # figured out.

On that bed lemme know if you want specific pics

Shame they bolted the running boards to the box...screwed that area up nice didn't it.
Is the front wall of the box straight? Mine has had something heavy hit it and bowed it up to the back wall of the cab. Definitely get floor pics, overall and at the seams/corners, tailpan area. Does the tailgate close nice? Mine is sprung somewhere, so it needs some attention, although I have another GM tailgate anyway.
How bout top of the bedsides too?

 

[blazinzuk]

So your 3.54s from the 70u should swap into the 70 hd housing.

Does that agree with what you have read?

 

[blazinzuk]

I will get pics of those things.

Front is straight. One of the pics is the tailpan

This is the tailpan pic



Well now I have an excuse to go start cleaning crap up.

 

[76zimmer]

So your 3.54s from the 70u should swap into the 70 hd housing.

Does that agree with what you have read?

Yes, this is what Randy's diffs told me over the phone....both have .625 offset, so he said the r/p will interchange into the 70HD carrier/housing.
BUT from what some have said on Pirate, there seems to be some confusion for me of the pinion bearing fitting into the HD housing?
And now I can't find the listing for the 70HD tru trac locker. figure if I'm gonna have it apart, Might as Well put the locker in it too.

 

[blazinzuk]

http://www.justdifferentials.com/TT915A670-p/tt915a670.htmhtm

One of the few I could find. Might wanna call and make sure it will work. Eaton only lists the e locker and detriot as available for the 70 hd

As far as the pinion bearing difference that's true but the pinion is the same. It's the housing that's different. That's all in the install kit

It's the carrier bearings that are the issue on the HD. They are wider than on the 70u or b.

 

[nvrenuf]

Spool it!!


(j/k )

 

[blazinzuk]

@Speedo

Hopefully he will chime in. Pretty sure he has forgotten more about the Dana 70 than I have ever known

 

[76zimmer]

Got the 6BT off the engine stand finally. Changed the rear main seal, then buttoned up the oil pan.
great tip from Luke on these engines....push the oil pan forward before tightening it down, as the trans adapter will hit the pan and possibly cause a leak other wise. After checking out the clearance between them, I put the trans adapter on then tightened down the pan, forcing it forward as much as practical .