I'm going to Moab in less than two weeks and I've been upgrading, modding my 79 40 for a couple months now. I've done some other easier mods like putting in a new OEM radiator and some new Aising hubs, but these were the big mods I've finished up in the last week. Please note these were way, way outside my comfort zone as I had never even changed my own oil before buying my 79 two years ago.
Saginaw PS conversion:
Holy crap this was a lot of work. I used a few threads on here as my bible as I tore out my stock stuff and replaced every single steering component. I got my Sag Pump bracket keyed pulley from Georg and everything else from Kurt at CruiserOutfitters. Highly, highly recommend using these guys for the conversion. Getting the right keyed pump, J20 steering box and belt were kind of a pain.
Also mocking everything up to get the right angle for the hole in the crossmember was also a pain. One tip, make sure you've sanded your stock steering shaft before putting on that shaft bearing, when they say it's a press fit, they weren't joking.
You don't really know how much clearance you're going to have until you finally attach the keyed steering shaft to your steering wheel. I had about 1/8 inch clearance so I ground on my motor mounts a bit until I felt comfortable with the space I had. Getting all four bolts to evenly thread through the steering box was also a pain, make sure you do this or your might cross thread or bind your bolts.
Also I needed a 1 1/2" drop pitman arm for an OME 2.5" lift and my relay rod is now perfectly parallel to my tie rod. I got all new TRE and rods from Kurt and am glad I did, it only took a few extra minutes to replace everything while it was all apart. Also use this Amazon.com: GearWrench 3916D Universal Ball Joint Separator: Home Improvement to remove the old ends. So so much easier than beating them with a pickle fork.
Results:
Once I finally had the whole thing plumbed, after some bending, and centered the steering wheel I took her out for her first drive. WOW. I should have done this mod two years ago. The steering feels like a modern vehicle, no slop at all. It tracked perfectly straight down the highway even with gusting winds. I can turn lock to lock on dry pavement with two fingers now on 33's. So glad I did the sag conversion, you can get parts anywhere and I'll be future proof when I go to 35s in a year or two. Tons and tons of work but totally worth it.
Aussie Locker install:
Watch this video: Now do exactly what you see this chick do and you'll be golden, but never, ever put a locker in a Dana 35 unless you want a crater where your diff used to be. This is the same chick with a grenaded Dana 35 after putting in an Aussie Also for kicks and giggles here's Hitler complaining about the turdy 5. Hitler blows up his Dana 35.
The toughest part for me on this was that I just didn't have the .006 clearance between the spacer and the pinion shaft. I had .005 but that was it, no matter how much I tried to squeeze any grease out. I ended up polishing the thrust washers to get .010 clearance and the rest was pretty straightforward. Getting that last c-clip in on the driveres side was a pain but if you use that 6 inch hanger tool in the video then you can move the PS spacer over and get the c-clip in.
Results: I'm honestly on the fence on this one. I'm considering taking it out and going back to an open diff after my Moab trip. I just don't like how it turns or drives locked up in the back. Maybe I'll get more used to it the more I drive, but I hate feeling so much of the back end all the time. I probably should have gone with an ARB, but I didn't have the $$$.
Rear Disc Conversion:
Besides the power steering conversion, this is by far the best mod I have ever done. I figured since I was already in the diff and taking axles out for the Aussie locker I might as well convert to disc in the back. I hate how my drum brakes would pull to the passenger side during hard, emergency stopping and lock up so easily. I've adjusted them and had them adjusted at a brake shop, but was never happy with them.
This mod was super easy. Like everyone on MUD is more mechanically inclined than me and it was still simplistic for me and my buddy to do. I got all my stuff from Poser who I would also recommend. We pulled the axles and than took the drum backing plate off with zero issues, it came off with a bump from a rubber mallet. Then we installed Poser's brackets the same way he did in his install thread, toward the front. I got a couple of 1985 Monte Carlo calipers from Napa for like $20 each and the cheap pads for like $15. I ground off that little bump on the housing of each caliper and the lip off from around where the banjo bolt goes. I screwed the caliper to the bracket with the pads loaded and everything fit perfect.
For the brake lines I went the lazy route and just bought a 40" and a 8" poly armour pre flared and pre nutted brake lines from Napa. These things are hand bendable and supposedly will never rust. I just used them to replace the old brake lines and screwed them into the soft brake lines from Poser's kit. That let me mock up where I wanted my tombstone tabs after attaching the soft line to caliper with the banjo bolt. My buddy welded the tabs in and two minutes later all the plumbing was done.
Then I went up front and removed the brake line from the rear circuit and removed that little plastic residual valve from under the big brass 24mm nut. Then I installed the prop valve from CityRacer and screwed everything back together. My buddy and I had one of those bleeder bottles and after about 5 minutes the whole rear circuit was bled and we were ready to roll.
Results:
Awesome, awesome awesome. Such a huge upgrade over those stupid drums. After adjusting the prop valve I can slam on the brakes from 50 mph and I get ZERO pulling one way or the other. I stop straight as an arrow now with reduced stopping distance as well. I can still lock up the rear if I push as hard as I can, but now even really aggressive stops are done with no locking in the rear. I feel like my rig is so much safer now.
Summary:
The best, easiest mod by far was the disc conversion. If you've ever thought about doing it, please call Poser ASAP and get it done. Seriously, ever 40 should have this done, it's too easy and too much of an upgrade not to. It took me all of a couple hours to do and I'm on the tard side of the mechanical skills spectrum. The sag conversion will be a lot more frustrating and time consuming but having power steering is great, especially if you plan on doing some serious wheeling. Plus you get to remove all the slop, which was nearly as big of an upgrade as adding the power. I'm still not sold on the Aussie, hopefully I can get used to it, but if not I guess I can scrape some money together for an ARB next year.
Also I'd like to thank Cruise Outfitters, Georg and Poser, couldn't have done it without their expertise and parts. Thanks
Saginaw PS conversion:
Holy crap this was a lot of work. I used a few threads on here as my bible as I tore out my stock stuff and replaced every single steering component. I got my Sag Pump bracket keyed pulley from Georg and everything else from Kurt at CruiserOutfitters. Highly, highly recommend using these guys for the conversion. Getting the right keyed pump, J20 steering box and belt were kind of a pain.
Also mocking everything up to get the right angle for the hole in the crossmember was also a pain. One tip, make sure you've sanded your stock steering shaft before putting on that shaft bearing, when they say it's a press fit, they weren't joking.
You don't really know how much clearance you're going to have until you finally attach the keyed steering shaft to your steering wheel. I had about 1/8 inch clearance so I ground on my motor mounts a bit until I felt comfortable with the space I had. Getting all four bolts to evenly thread through the steering box was also a pain, make sure you do this or your might cross thread or bind your bolts.
Also I needed a 1 1/2" drop pitman arm for an OME 2.5" lift and my relay rod is now perfectly parallel to my tie rod. I got all new TRE and rods from Kurt and am glad I did, it only took a few extra minutes to replace everything while it was all apart. Also use this Amazon.com: GearWrench 3916D Universal Ball Joint Separator: Home Improvement to remove the old ends. So so much easier than beating them with a pickle fork.
Results:
Once I finally had the whole thing plumbed, after some bending, and centered the steering wheel I took her out for her first drive. WOW. I should have done this mod two years ago. The steering feels like a modern vehicle, no slop at all. It tracked perfectly straight down the highway even with gusting winds. I can turn lock to lock on dry pavement with two fingers now on 33's. So glad I did the sag conversion, you can get parts anywhere and I'll be future proof when I go to 35s in a year or two. Tons and tons of work but totally worth it.
Aussie Locker install:
Watch this video: Now do exactly what you see this chick do and you'll be golden, but never, ever put a locker in a Dana 35 unless you want a crater where your diff used to be. This is the same chick with a grenaded Dana 35 after putting in an Aussie Also for kicks and giggles here's Hitler complaining about the turdy 5. Hitler blows up his Dana 35.
The toughest part for me on this was that I just didn't have the .006 clearance between the spacer and the pinion shaft. I had .005 but that was it, no matter how much I tried to squeeze any grease out. I ended up polishing the thrust washers to get .010 clearance and the rest was pretty straightforward. Getting that last c-clip in on the driveres side was a pain but if you use that 6 inch hanger tool in the video then you can move the PS spacer over and get the c-clip in.
Results: I'm honestly on the fence on this one. I'm considering taking it out and going back to an open diff after my Moab trip. I just don't like how it turns or drives locked up in the back. Maybe I'll get more used to it the more I drive, but I hate feeling so much of the back end all the time. I probably should have gone with an ARB, but I didn't have the $$$.
Rear Disc Conversion:
Besides the power steering conversion, this is by far the best mod I have ever done. I figured since I was already in the diff and taking axles out for the Aussie locker I might as well convert to disc in the back. I hate how my drum brakes would pull to the passenger side during hard, emergency stopping and lock up so easily. I've adjusted them and had them adjusted at a brake shop, but was never happy with them.
This mod was super easy. Like everyone on MUD is more mechanically inclined than me and it was still simplistic for me and my buddy to do. I got all my stuff from Poser who I would also recommend. We pulled the axles and than took the drum backing plate off with zero issues, it came off with a bump from a rubber mallet. Then we installed Poser's brackets the same way he did in his install thread, toward the front. I got a couple of 1985 Monte Carlo calipers from Napa for like $20 each and the cheap pads for like $15. I ground off that little bump on the housing of each caliper and the lip off from around where the banjo bolt goes. I screwed the caliper to the bracket with the pads loaded and everything fit perfect.
For the brake lines I went the lazy route and just bought a 40" and a 8" poly armour pre flared and pre nutted brake lines from Napa. These things are hand bendable and supposedly will never rust. I just used them to replace the old brake lines and screwed them into the soft brake lines from Poser's kit. That let me mock up where I wanted my tombstone tabs after attaching the soft line to caliper with the banjo bolt. My buddy welded the tabs in and two minutes later all the plumbing was done.
Then I went up front and removed the brake line from the rear circuit and removed that little plastic residual valve from under the big brass 24mm nut. Then I installed the prop valve from CityRacer and screwed everything back together. My buddy and I had one of those bleeder bottles and after about 5 minutes the whole rear circuit was bled and we were ready to roll.
Results:
Awesome, awesome awesome. Such a huge upgrade over those stupid drums. After adjusting the prop valve I can slam on the brakes from 50 mph and I get ZERO pulling one way or the other. I stop straight as an arrow now with reduced stopping distance as well. I can still lock up the rear if I push as hard as I can, but now even really aggressive stops are done with no locking in the rear. I feel like my rig is so much safer now.
Summary:
The best, easiest mod by far was the disc conversion. If you've ever thought about doing it, please call Poser ASAP and get it done. Seriously, ever 40 should have this done, it's too easy and too much of an upgrade not to. It took me all of a couple hours to do and I'm on the tard side of the mechanical skills spectrum. The sag conversion will be a lot more frustrating and time consuming but having power steering is great, especially if you plan on doing some serious wheeling. Plus you get to remove all the slop, which was nearly as big of an upgrade as adding the power. I'm still not sold on the Aussie, hopefully I can get used to it, but if not I guess I can scrape some money together for an ARB next year.
Also I'd like to thank Cruise Outfitters, Georg and Poser, couldn't have done it without their expertise and parts. Thanks
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