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Changed idler arm, idler arm bracket, and pitman arm. Had a hell of a time finding a pitman arm puller that was big enough, ended up having to use a 2 jaw 5 ton puller from autozone. Even with that I had a hell of a time getting the pitman arm off. Tried twice, then gave up and got the grinder, hammer and chisel punches out. Couldn't it to brake free that way either. So I tried one more time with the 2 jaw puller, had to use a 24" 1/2 drive breaker bar, but she finally broke free. The bolts holding the puller together are bent badly, probably wouldn't have taken much more before the puller broke.
 

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Changed idler arm, idler arm bracket, and pitman arm. Had a hell of a time finding a pitman arm puller that was big enough, ended up having to use a 2 jaw 5 ton puller from autozone. Even with that I had a hell of a time getting the pitman arm off. Tried twice, then gave up and got the grinder, hammer and chisel punches out. Couldn't it to brake free that way either. So I tried one more time with the 2 jaw puller, had to use a 24" 1/2 drive breaker bar, but she finally broke free. The bolts holding the puller together are bent badly, probably wouldn't have taken much more before the puller broke.

Local O'reillys that does tool rental has several of the pitman arm pullers. Every time i use one, out comes the grinder and it gets "massaged" a little since the jaws are forged just a bit off. Still need the grinder on the arm to get the thing off. 1/2" impact hammering away on it will not get it off. Have tried 18" breaker bar and both legs pulling on it. I know the puller was in a bind. With all that load on the arm, a little grader action and it eventually popped off.
 

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Local O'reillys that does tool rental has several of the pitman arm pullers. Every time i use one, out comes the grinder and it gets "massaged" a little since the jaws are forged just a bit off. Still need the grinder on the arm to get the thing off. 1/2" impact hammering away on it will not get it off. Have tried 18" breaker bar and both legs pulling on it. I know the puller was in a bind. With all that load on the arm, a little grader action and it eventually popped off.
I bought just a standard size puller that you would rent from one of the parts stores, it was way too small. Then found the biggest one that I could find online, the Lisle 41970, designed for 05+ super duties. It was also still too small. When I did my LLY I just rented the standard size puller from Advance, and it was fine. The LML is a giant compared. The LLY pitman arm nut is 1-5/16, the lml pitman arm nut is 1-13/16...
 

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I bought just a standard size puller that you would rent from one of the parts stores, it was way too small. Then found the biggest one that I could find online, the Lisle 41970, designed for 05+ super duties. It was also still too small. When I did my LLY I just rented the standard size puller from Advance, and it was fine. The LML is a giant compared. The LLY pitman arm nut is 1-5/16, the lml pitman arm nut is 1-13/16...
Did not realize they made them that much bigger.
 

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I don't know why they put those pitman arms on so tight but I have fought many to the death. Sometimes the only solution is to put the puller on as tight as I dare and then grind a slot in the arm with a cutoff grinder. I'm sure there is a better way but who can afford a $2000 tool for such a thing.
 

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When installing tracbars, is it best to match the driveshaft angle or have them longer? I’m just stuck deciding how long I want these bars. They are just mocked up right now. I’d prefer a more comfortable ride. Any input from the board?
Looks like you never got a reply on this so I'll chime in.

The short answer is that to minimize vibration and other complications you want to have the t-case output shaft and the pinion shaft at the same angle to the ground at all times. You want to adjust your linkage so that the two angles are the same in the normal running condition. If it can be arranged you want them to stay that way regardless of suspension movement.

For the longer answer keep reading.

Ideally you want the drive shaft to stay lined up so that it doesn't even need u-joints. When I was a kid we had a 1956 Buick Century that had a rear end with a really long pinion gear. The shaft of the pinion gear reached all of the way up to the rear of the transmission. It was enclosed in a pipe extension on the nose of the differential which formed a part of the rear suspension by keeping the differential all lined up. This setup only had a u-joint at the transmission and since the pinion gear was about 6 feet long and the suspension only had about 8 inches of movement the u-joint angles were small enough that it worked just fine.

A typical Cardan type universal joint (the type we all know and hate) is not constant velocity. That is, if the input shaft turns at a constant angular velocity the output shaft will only also turn at a constant velocity if the shaft is straight. If the shaft bends at the u-joint then the output shaft will speed up and slow down 4 times per revolution. This change in velocity is small if the angle is small but as the angle increases it becomes much higher much faster than the the change in angle might suggest. There is a formula to calculate this but we won't talk about the math here.

The change in velocity of the drive shaft is experienced as a vibration in the truck at 4 times the drive shaft rotational speed. If you are going down the road at 60 MPH with 40 inch tall tires and 3.5: gears in the differential the shaft will be vibrating about 30 cycles per second. Compare this to wall a/c power at 60 cps which produces hum in a lot of things. The vibration of the drive shaft would be about an octave below the hum in a cheap stereo.

There are several ways to get around this change in velocity. The first is to use 2 Cardan joints in a single assembly. This is called a double Cardan joint. You see it a lot in the front drive shafts at the t-case on many trucks. Occasionally you see it in the rear drive shaft of some vehicles. They are also common in steering shafts between the steering gear and the steering wheel.

If two Cardan type u-joints are aligned properly then the acceleration produced in the drive shaft by the first joint is reversed by the second joint and the output is constant velocity. The shaft between the joints will be vibrating like mad but the rest of the truck will not notice it as long as the drive shaft has very little mass. If the drive shaft is really heavy though something has to accelerate all that mass so the forces are transmitted to the vehicle. This is one reason to use a two piece drive shaft. So that one shaft can react against the other and the vibrations counter each other, leaving the vehicle undisturbed.

If the joints are not aligned properly then the vibration is amplified. This can happen with a 2 piece drive shaft that has a spline in the middle. If the spline is assembled wrong then the u-joints will be out of "phase" and it will vibrate. In a double Cardan joint the two joints are made into a single assembly there is no chance of a phase problem and the intermediate shaft that still vibrates is merely the two yokes of the two joints. Since the intermediate shaft is so light there is little vibration to transfer. This is kind of like having a two piece drive shaft but one of the shafts is really short.

A second way to eliminate the problems associated with ordinary u-joints is to use a constant velocity joint instead. There are several types of these but the most common these days is called a Rzeppa joint. Rz in Poland is pronounced like sh here. Alfred H. Rzeppa was an American mathematician/engineer of Polish decent working for Ford in 1926 when he came up with this design. You see these all of the time on the end of CV shafts on front drives. You have two of them on the front of your truck right now.

In an Rzeppa joint the only thing that accelerates is the balls between the inner hub and the outer race. They do this in pairs, one speeding up while the other slows down, so that outside the joint it seems that all is smoothness. The down side to Rzeppa joints is they cost a bit more to make, they are heavier for the power they transmit and they can't bend as far as a double Cardan joint. That is rarely a problem but is worth knowing about.

If Cardan type u-joints are to be used on a shaft the bends twice then the joints may have to be phased in a different way. For example, I changed out the steering column on an old truck once and replaced the manual steering gear with a power steering gear located in a different place. To get the steering shaft to connect to the steering gear without having the steering wheel in an odd location I had to have the steering shaft bend in 3 places and at pretty sharp angles. My first attempt resulted in the steering doing almost nothing for a quarter turn of the wheel and then turning way over in the next quarter turn. It was "interesting". After some thought I reoriented the u-joints and gave it another try. It worked very well this time. I'm sure at 1000 RPM it would still have been a vibrator but at typical steering wheel speed it was fine.

Just for what it's worth, double Cardan joints can be made one inside the other. This very much resembles the gimbals on a gyroscope. The outer joint doesn't exactly have a cross and the inner joint has no yoke. The connection between the two joints is a ring with stubs on the outside for one joint and ninety degrees away on the inside of the ring are stubs for the other joint. It's a neat solution when there is room. The part that accelerates is just the ring between the two joints.

If you really want to understand all of this then look here:

https://en.wikipedia.org/wiki/Constant-velocity_joint#Double_Cardan

https://en.wikipedia.org/wiki/Universal_joint
 

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Did the Allison deep pan, and Trans Go Jr. today. Did the CAT filter a couple months back.
 

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Re-flashed my ECM with the SOTF tunes from PPEI. Then I added the switch and pulled the ECM plug in order to add the two wires into there.

Haven't taken it for a drive yet, but did start her up just to make sure she's a goer!!

She's a GOER alright!!!

Now I'm looking forward to being able to switch tunes whenever I want/need to.

Roachie
Kadina, SA
Australia
 

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Foam cannon washed it, then did a coat of blackfire synthetic spray wax, got that free as a 4oz sample size with my last order from autogeek.com

Probably will be the last pictures taken before window tint on Saturday.


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Foam cannon washed it, then did a coat of blackfire synthetic spray wax, got that free as a 4oz sample size with my last order from autogeek.com

Probably will be the last pictures taken before window tint on Saturday.


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Looks good Justin

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Looks good Justin

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I think I might debadge the 2500hd badges yet. What do you think?

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I think I might debadge the 2500hd badges yet. What do you think?

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I've been thinking of some debadging because the middle of the passenger door bowtie popped off, but was thinking I'd leave the 2500HD.

Not sure yet

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Thanks for the reply... Air filter is clean and I cleaned the MAF sensor last year when I put the Banks intake on. Pretty sure the MAP sensor is good also as I messed with that during the EGR delete. And I know it's not fuel related because actual vs desired rail pressure is always pretty much spot on. I was just comparing what it felt like when it happens when I used the fuel line analogy (it's like someone is pinching the boost tubes). If I really get onto the pedal, I can hit 30 psi. That's why it's so weird, because it only happens under NORMAL driving and acceleration. Just loses boost as soon as I press the throttle more instead of builds up, so it's complete opposite of what a turbo should do.


I used to monitor vane position, but since my CTS touch screen has been messed up I haven't changed the gauges in a good while (I can't navigate through the CTS anymore so I just leave it where it's at). But yes your issue sounds just like mine!! I wonder if it's in the tuning. Do you have PPEI by chance??
Why yes I do happen to have PPEI efi tunes, I usually run 30hp
 

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Thanks for the response. I should also add that when the trucks engine temp is cold (driving after first start up) the boost builds fine, its only after the engine is warm does this happen, which is within 5-10 minutes of driving. But to answer your question, I am running a street tune but they are built trans tunes so I would say maybe 120HP. I will try to mess with my CTS again to view those parameters. Can my Autocal do that also ?

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The AutoCal might I haven't used it much for pids with having the CTS2.
The pids have to be programmed in it, in order for it to read what your looking for.

How does the turbo and boost react on a lower hp tune?
I'm a non believer with slamming big hp to these/any engine, to many quirky things will happen.

I'm running ATP 40hp Towtune with turbo brake, no delay at all, instant power and instant rise in boost max boost 32, no matter what speed I'm going.
 

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The AutoCal might I haven't used it much for pids with having the CTS2.
The pids have to be programmed in it, in order for it to read what your looking for.

How does the turbo and boost react on a lower hp tune?
I'm a non believer with slamming big hp to these/any engine, to many quirky things will happen.

I'm running ATP 40hp Towtune with turbo brake, no delay at all, instant power and instant rise in boost max boost 32, no matter what speed I'm going.
Yeah its definitely weird. Falls on its face in regards to boost but fuel rail pressure and desired pressure is almost spot on so I know it's not fuel related. Here are a few pics of what you talked about in an earlier post. The first one is at idle in park and as you can see the baro and map are within 1, but the second picture is while driving down the road and the numbers get farther apart and at one point map hit 17. Baro stays constant at 14.5. Is that supposed to happen while driving? Don't get me wrong, when I throttle down its builds great boost, around 30. But driving normally and then accelerating normally it actually loses boost instead of builds boost. Got me stumped.


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Its when your engine is idling you want those numbers, the MAP will jump up as your driving.
I would drive around a while on a lower HP tune and see what happens, and how everything reacts.
Big tunes are not always the better choice.
 

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Getting ready for a 3 week camping trip to AZ and NM. Lots of hills my truck has not yet experienced so I thought Id do my best to insure no heating and power problems. To that end I:

1. Replaced both 1/2" rubber fuel lines with 1/2" blue fuel hose. The lower one bey the tranny was easy. The upper one was the worst, it was clearly kinked, which is why I started the process in the first place.

It necessitated removing the tire, fender liner, and left intercooler pipe to access the hose. NOT difficult, just a Dmax.

2. Took my cooling stack apart and cleaned it with air and fresh water.

Just before we leave I will change the oil&filter and the fuel filters, lube the front end and be ready to go.
 
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