Re: 75 Dually build
 

I ran mine with a 4.10 gear ratio for a few years and eventually went to 3.55s. Even in Overdrive and going down a big hill I couldn't get mine over 65 MPH. Keep up the good work on this and the cab swap project. :metal: :metal:

Re: 75 Dually build
 

I did find a 3.42 ring and pinion today that is the lowest you can go on a 10.5" 14 bolt. It wasn't to bad at $281 from Summit Racing, but I just want to fix mine right now and then see how it does with the Cummins in it. If I don't like it then I can always change it after the fact. A ring change on these rear ends is not that hard, so we shall see...

The cab swap project is coming along nicely, I've got a much nicer weekend weather wise to get a couple things done on it too. Should have some more updates on that soon.

Re: 75 Dually build
 

Last night my best friend brought by some yellow grease from work, and this morning I did the yellow grease thingy on the gears. Sent the pictures you see below to a very good friend of mine in Idaho who is an expert on gears, and he said leave it alone.

So after the good news I ordered all the bearings, seals, etc... to get this truck back on the road. They should be in by mid week, and I hope to be able to have it back out by next weekend.

It is great to have good friends who help out!:metal:

Stay tuned!

Re: 75 Dually build
 

Is this rearend project delaying your 68 gmc project? LST is fastly approaching!

Re: 75 Dually build
 

Yes, yes it is! However I got a bad cold over Christmas and just got rid of it so my time line is so out of wack it is not even funny. I would like to take the 68, but won't worry if it does not go this year. The Dually has to go no matter what.

Re: 75 Dually build
 

Ahhhh ok. I thought the 68 was your main priority for LST. Either way I hope you are able to take something. I’m trying to scramble and see if I can put together a 61 Apache dually in time for c10sinthepark

Re: 75 Dually build
 

Originally the 68 kinda was the main focus, after I caught that cold and I knew from last year that the dually needed the rear end fixed before LST, I made up my mind that I better make sure that one of them went so I had a ride there. That pushed the dually to the top of the list.

Now I'm not writing off the 68, but I won't get all torqued up if it does not happen. In fact I have some things I found out this weekend that is really going to make that ride sit a bit lower, and some items that will help speed up the build process. For that check out that build here: http://67-72chevytrucks.com/vboard/s...d.php?t=747558 Also I know I want it completed for C10's in the park too. We need to get a bunch of guys from this part of the world and do a really cool road trip to that event. I bet it would be cool to make that happen!

Now about your 61 Apache... That would be a super cool ride for C10's in the park!

Re: 75 Dually build
 

Yeah, just so much to figure out and I still have to get a title for it first.

Re: 75 Dually build
 

How tall are your tires currently? I think you will find out that 4.10s will suck with the cummins even with OD unless your tires are 33" tall.

Re: 75 Dually build
 

My tires are 32" tall. So we will just have to see what that is actually like. I really want to change it over to a 3.42 ratio because that is the lowest that is available for a 14 bolt 10.5" GM rear end. I just know how much Santa beat me up, and I've got other things I want to spend money on right now.

We shall see...

Re: 75 Dually build
 

I got the diff and the pinion out tonight. Now it is time to get the new bearings pressed on and get this truck back on the road. I have a list of items I want done before we head off to LST, so it is time to get busy and check them all off before we head out.

42 days 11 hours 43 minutes and 28 seconds!

Time to get busy!

Stay tuned!

Re: 75 Dually build
 

So just a quick note. We have been working on the truck! Ok in between nasty head colds (the flu has been running around Lubbock like wild fire!), my job (Imagine that!), and life in general. I have had a bunch of good friends helping me get a ton of small items completed.

So far we had a couple of starts and stops with the diff update. Some bearings were wrong in the kit I got, but finally we got it all figured out and got them all installed today. I should have the diff and the rear end buttoned up, along with the watts link reinstalled by the end of the week. Crossing my fingers!

Then we should be on to finishing up the interior. I am trying to update the seats, a center console, and finish the stereo system. A lot of small items to get checked off the list before we leave for LST.

So much to do and so little time, typical!

Stay tuned!;)

Re: 75 Dually build
 

The diff and the pinion are in!!! Now to rest my sore back... Tomorrow I will run the patterns on the engagement, and then button it all up.

Gotta get the watts link mounted back up too. Going to make it removable this time. Ah well live and learn!

Stay tuned!

Re: 75 Dually build
 

So tonight I worked on getting the watts link reinstalled. Nothing very special I just made mounting tabs out of 1/4" plate, welded them to the rear end housing and then drilled a 1/2" hole through the tabs and the link arm. Shot some black paint on the metal parts and bolted everything back up. Sounds simple but it was actually a lot of work to get everything perfect and to line up correctly. Now if I ever have any issues with the rear end again the watts link can be unbolted and moved out of the way for servicing. Yeah, yeah, yeah I know I should have done this in the first place! Ah well live and learn...:lol:

My friend and I went during lunch today to the upholstery shop and picked up the vinyl material for the door speaker pods and the center console we are building. I did take a pic of the seats that I'm installing so we could match the material. These are late 80's Chevy buckets and a rear 60/40 split. I have always liked these seats, they are very comfortable, and I think they look great. I can't wait to get them installed and moving towards getting this truck ready for LST.

Stay tuned!;)

Re: 75 Dually build
 

So I took the truck out for a quick spin and the results were excellent. Now to concentrate on the interior make over. My friend is getting the new lower door panels ready for the 6.75 inch speakers. This weekend I will get on the construction of the new center console.

Getting closer to being ready.

Gonna be fun! Stay tuned!

Re: 75 Dually build
 

Sweeeeeet!

Re: 75 Dually build
 

My last mechanical with the truck was finished tonight! YES! Now on to the interior...

I have had a drive line vibration at around 70 MPH for quite some time. Because this truck has a 4:10 ring I don't like to rev this 454 too much and possibly hurt it. So I try to keep the top speed down a bit. The pic below is an older pic from when I was doing the 4 link, but you can see the angle gauge that I have used, and it is really accurate.

What I did was investigate all the drive line angles as they sat right now, and then I did some research on what the correct angles should be for the entire drive line. The hyperlink below is from the Spicer webpage, it is really good to use if you are doing any suspension changes. You click on how many driveshafts you have (mine obviously has 2) and then you enter the measured angles and it gives you the working angles for each u-joint.

For those of you who have never set your drive line angles there are some really good YouTube videos that explain how all that works. Basically you have the driveshaft angle and then the angle the u-joint is positioned at. The relationship between these two is very important to keep the u-joints happy and functioning properly, and the relationship of the opposing u-joint and 2nd driveshaft (if you have a 2 piece driveshaft) need to be in harmony. In the end what you need is to make sure the working angles between the shafts and the u-joints are very close to the same angle. That way as one u-joint moves it's opposing u-joint cancels out the vibration and movement of the other u-joint. The closer you get the working angles to match the less vibration you will have.

I'm so happy the way I set up the 4 link. It gives me so much flexibility to move the pinion angle to whatever is required. What I found out was I only had to move the pinion angle about 0.6 degrees up. This did not take all the vibration out, but a lot of it was dealt with. What needs to happen next if I decide to take this any further is I need to move the center carrier bearing up to lessen the driveshaft angles. That would close down the working angle in the center and thus make the whole system work a lot better. However for now I will take this as a win and come back to it in the future.

http://spicerparts.com/calculators/d...gle-calculator

We are in the last 2 weeks of the LST crunch! Interior is next...

Stay tuned!

Re: 75 Dually build
 

6° change??

What was your pinion set at?

Re: 75 Dually build
 

No 0.6 degrees Scoti :lol: Glad we got that cleared up!

Re: 75 Dually build
 

Glamour shot! It needed a bath soooo bad! We have had a ton of dust storms lately, and it got covered in dust and dirt while getting repaired.

But I took it in today to get the annual inspection, and it drives so nice now. Can't wait to cruise it to LST!

Oh yeah that is going to be in 13 days 11 hours and 9 seconds, but who's counting...

Stay tuned!;)

Re: 75 Dually build
 

It is so on! Today after church I took out the old seats and started to trial fit the new seats. I started with the 60/40 split pair. Um... They are going to take a bunch of work. I'm hoping that the front seats will go in much easier. What I have done so far is just bolt down one corner and see what it is going to take to get them to fit. Lots as it turns out...:lol: I'm thinking about just making my own frames, I think that will be less work than redoing all the GM stuff. The issue is they are way to high. I tried to sit in them at the height that you see in the picture below, but my head just touches the ceiling. Basically they are not even close to right, so I guess I have to get the saw and the welder out!

Stay tuned!;)

Re: 75 Dually build
 

Dude, you are running out of time...

Re: 75 Dually build
 

Nice to hear you're getting the vibration removed in it. To add to the operating angles, if you don't have enough operating angle on the u joints, they can prematurely fail as well. I've had that same battle with newer seat mounts. They are always to high it seems. Making new frames/mounts is what I have done too. Definitely faster. Good luck getting them done in time!

Re: 75 Dually build
 

Yeah I know, I know... But we will be there this year! I look forward to seeing that wing!! Remember I owe you dinner.

We are going to take our time driving to the show this year. I just don't want to run into any issues.

The seats are just about done! I will have them finished tonight, and hopefully painted and ready to be finally installed for the last time.

Wait until you see the center console, and the speaker door pods we are making. They are going to be really nice!

Re: 75 Dually build
 

I have been in the shop after work every night until late trying to get everything buttoned up. The rear seats have been a lot of work to get right. The pic below shows them in their final position. There is very little left of the original frames. To get these seats to fit the frames had to be cut, sliced, and almost diced to get them to fit and work. The cool thing is that they have the same function as the original frames, just changed to fit these floor pans.

The last thing I did tonight was paint the rear frames black to match the carpet and not make them stand out so much. I bet a ton of people will look at this and think "yeah so you put stock seats back in it, so what?" Never knowing just how much work it was to get them to look like they belonged from the factory.

The front seats are all ready to go, they just need to be bolted down in their new homes. I have to wait until the new center console is finished and installed before I can check that off my list. BTW the new center console is off the charts!

LST - 7 days, 7 hours, 51 minutes! But again who is counting....

Stay tuned!;)