Builds Dirty Koala Build - Cummins 6BT + NV4500 + HF2AV Swap (1 Viewer)

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Back in the middle of December while cruising along the highway at about about 70+ mph I suddenly lost 90% of control of the truck. The cruiser was shaking violent and I had almost no steering. I managed to get the truck across 3 lanes and safely stopped on the shoulder without hitting anything...someone was watching over me that day. I had managed to rip the upper front panhard mount off the chassis.

This was caused by three things:
  1. 21 years of metal fatigue.
  2. Lots of punishment that I have put the truck through this year....high speed desert romping primarily
  3. Builder (Me) error. When I cut out the steering cross member brace to clearance the 6BT, I had intended to go back and plate the frame and make a removable cross member so that oil pan removal wouldn't require engine removal....I never went back and did either of those things....a recipe for disaster.
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I had the truck towed to my good buddy @bryson house for some custom fab work.

The remainder of the mount had to get ripped off the chassis, but cleaned up really nicely.
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The panhard bushings had seen better days...so I picked up a pair of front and rear rubber bushings from @cruiseroutfit
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The outside of the frame was plated with two layers of 3/16" fish plates. This 3/8" also serves to space my steering box out which was required for clearance of the 6BT timing cover. I originally just made a 3/8" spacer plate...this is much better. The outside tube/mount was also fully welded (OEM is 3 spot welds).

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The inside of the frame was repaired where the bracket was torn off. Another custom fish plate was fully welded and the cleaned up mount was reattached to the beefed up chassis.
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A pair of custom machined Interlocking Tube Clamps were made to build the foundation for a strong removable cross member brace. These were welded to the factory cross member stubs that I had left when I cut out the tube.
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Front bushings need replacement really badly...rear not so much, but they got replaced anyway.
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And here is the piece de resistance, the removable cross member brace. I am very excited to have this beast back on the road.

The tube is made of two pieces of DOM. The inner tube is 1.25" .188 wall tube, the outer sleeve tube in the center section is 1.5" .120 wall. One half of the interlocking tube clamps were welded to either end of the 1.25" tube. Both tubes had a section scalloped out to clearance the 6BT Oil pan and then welded together and filled in with plate. A .25" fin truss was added to the bottom to increase strength.
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That's a nice brace, on mine we just cut 7/16 " out of the brace and a little heat bend it down 1" and welded some gussets, seems to work out , I am glad you did not get in a accident . On cold day's here I use my block heater, I was told that if you bump the timing up a little it help with the smoke, I have yet to hook up my grid heater I will one day
 
I have been meaning to go back to page 1 of this thread and update the index with all the progress over the past couple years. Well it took all night, but I got it updated...should make it easier to find most things documented in here.

Index Page Link
 
Back in the middle of December while cruising along the highway at about about 70+ mph I suddenly lost 90% of control of the truck. The cruiser was shaking violent and I had almost no steering. I managed to get the truck across 3 lanes and safely stopped on the shoulder without hitting anything...someone was watching over me that day. I had managed to rip the upper front panhard mount off the chassis.

This was caused by three things:
  1. 21 years of metal fatigue.
  2. Lots of punishment that I have put the truck through this year....high speed desert romping primarily
  3. Builder (Me) error. When I cut out the steering cross member brace to clearance the 6BT, I had intended to go back and plate the frame and make a removable cross member so that oil pan removal wouldn't require engine removal....I never went back and did either of those things....a recipe for disaster.
View attachment 1902702

I had the truck towed to my good buddy @bryson house for some custom fab work.

The remainder of the mount had to get ripped off the chassis, but cleaned up really nicely.
View attachment 1902703

View attachment 1902720

View attachment 1902719

The panhard bushings had seen better days...so I picked up a pair of front and rear rubber bushings from @cruiseroutfit
View attachment 1902705
Glad you came out ok. If it's alright, i'll learn from your mistake and not leave out the brace on my mine. Was going to worry about it later also. Not now
 
rn from your mistake and not leave out the brace on my mine. Was going to worry ab
Yeah definitely don't just cut it out. The cross brace is a key component of the front panhard mount strength.
 
That's a nice brace, on mine we just cut 7/16 " out of the brace and a little heat bend it down 1" and welded some gussets, seems to work out , I am glad you did not get in a accident . On cold day's here I use my block heater, I was told that if you bump the timing up a little it help with the smoke, I have yet to hook up my grid heater I will one day
Yeah the brace is pretty slick. I really wanted a removable brace so that oil pan removal isn't a major project. I am actually going to have to replace the oil pan at some point since the axle dented it when the panhard mount ripped off. I should have done this a long time ago. When I get back to UT I am diving into the fueling system. In theory the timing was set at 16 degrees by the engine builder (factory for that 215 pump is 13.5). I am going to check the timing and adjust if needed. Working theory at the moment is I just haven't been letting my grid heaters cycle for long enough before starting as Bryson didn't have any trouble starting her in freezing temps.
 
So I was getting tired of the old ARB and wanted something a little more unique to spruce up the front end....time to go custom.

The high clearance approach angle requires notching off the leading lower edge of the frame horns, which also meant notching and capping the intercooler.
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Bumper is all welded up minus the tube work and light tabs..loving this look.
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Looks familiar! :cheers:
 
To solve the engagement issue, I took the pushrod pin and adjuster out, cut the two welds on the adjuster, welded a thick nut between to two halves of the adjuster and put it back together.
View attachment 1280843

I ran through all gears with the motor running without any grinding, so it appears I am getting full clutch engagement.

Could you elaborate on this? I'm not very familiar with clutch hydraulics. You were essentially making the Toyota master cylinder pushrod longer?
 
Could you elaborate on this? I'm not very familiar with clutch hydraulics. You were essentially making the Toyota master cylinder pushrod longer?
Yes that is correct, I made the master cylinder push rod a little longer, so that I could get a little more movement out of the slave cylinder push rod. This was required to get full clutch engagement.
 
You don't happen to have the PNs, specs, or source for the 90 elbow and A/C cutout switch adapters, do you?

Pulled the Cummins temp sensor from the rear drivers side of the head and installed a 90 elbow that then holds both the Toyota coolant temp sensor and a nipple fitting for the heater control valve inlet hose.
View attachment 1233748

Removed the 1/2" NPT plug from the head under the intake manifold and using an adapter, installed the Toyota A/C cutout switch.
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Also since I my conversion I have earned back $885 dollars in fuel savings over 31,000 miles.
You don't happen to have the PNs, specs, or source for the 90 elbow and A/C cutout switch adapters, do you?
The 90 elbow needs to be drilled and tapped to the right size threads...I think the nipple side was 1/2" NPT...I can't recall what the toyota sensor thread pitch was though.
 
I picked up and wired in a 2nd Ford solenoid and the truck is starting up fine now...fingers crossed it stays that way. The primary issue is that the Toyota harness is providing such low voltage 9.5v that it doesn't take much current draw to overwhelm it.

I have the Toyota start wire activating the 1st Ford solenoid, which then powers up the starter and a jumper wire to activate the 2nd ford solenoid. The 2nd solenoid, then powers up the trigger wire on the fuel shutoff pull circuit.

Did this ultimately fix your starting/wiring issue?
 

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