'75 J-20 service truck

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jaber
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Re: '75 J-20 service truck

Post by jaber »

Not yet, still need the vents for the dash and the hose kit to get it in. I've been running my butt off this summer and have not even got it mapped out yet. I know, shame on me...
I do have to say that I've been running this truck daily and with 17 mpg and the conversations I've been having, for my use, it's one of the best decisions I've made. Only problem I've had lately is keeping tires under it... :-bd
Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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tedlovesjeeps71
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Re: '75 J-20 service truck

Post by tedlovesjeeps71 »

jaber wrote:My trans kept leaving little drips under the rear aluminum case and the last couple weeks it turned into small puddles. Found a cast replacement on Ebay for $85 shipped and no more worrying about its fluid level. Did the seals in t case while it was out. Also found it already has a 5th gear lock nut, so that's another worry off my mind...

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Did you use a gasket or rtv for the new housing? I ordered the same thing for my scrambler. Haven't had time to install it yet.

Also, I read that some/many of these steel housings had bad bores. Not sure if that issue ever got resolved but it's worth reading up on.
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jaber
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Re: '75 J-20 service truck

Post by jaber »

Oh sure, NOW you tell me about the bad bores...
So far so good, no gasket, just black rtv. It's nice pulling into a customer's drive and not leave a mark.
My problem is that I've done too much reading on the NV4500. It's a medium duty trans in a heavy duty application. I found a thread on one of the Dodge forums that talks about finding an SAE#2 rear engine adapter and putting an Eaton/ Fuller 6 spd into it that will handle 500k be for needing repairs. Heres the thread if you have a couple days to read...

https://www.cumminsforum.com/forum/98-5 ... uller.html
Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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tedlovesjeeps71
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Re: '75 J-20 service truck

Post by tedlovesjeeps71 »

jaber wrote:Oh sure, NOW you tell me about the bad bores...
So far so good, no gasket, just black rtv. It's nice pulling into a customer's drive and not leave a mark.
My problem is that I've done too much reading on the NV4500. It's a medium duty trans in a heavy duty application. I found a thread on one of the Dodge forums that talks about finding an SAE#2 rear engine adapter and putting an Eaton/ Fuller 6 spd into it that will handle 500k be for needing repairs. Heres the thread if you have a couple days to read...

https://www.cumminsforum.com/forum/98-5 ... uller.html
Sowwy. Image

I think the 4500 is a good transmission. It has flaws but those can be addressed. My understanding is the lost 5th gear usually reared its head when people towed very heavily and used the cruise control often. The load/unload events caused the shaft to hourglass, the nut to loosen then fall off, and the. 5th gear would slip out of position. Hard to fix a previously "used" that is already showing signs but a fresh build and the "fix" installed should do the trick.
Next n line is often the 5600 but cost, size, and weight make that a hard choice.
I read some on the Clark conversion too. It sounds good. Finding one and living with the wider shift pattern where the biggest complaints.
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jaber
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Re: '75 J-20 service truck

Post by jaber »

It was nice to see the aftermarket 5th gear nut already on mine when I switched the cover. Makes for mo re piece of mind...
My understanding is that the 5600 is notorious for snapping output shafts...
Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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tedlovesjeeps71
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Re: '75 J-20 service truck

Post by tedlovesjeeps71 »

jaber wrote:It was nice to see the aftermarket 5th gear nut already on mine when I switched the cover. Makes for mo re piece of mind...
My understanding is that the 5600 is notorious for snapping output shafts...
Not saying it isn't true... I'd just be curious as to the conditions that cause it to snap. There's more than a lot of guys running turned up Cummins towing crazy heavy stuff. IMHO, if your rolling 800^ tq and towing 20k+ and lose a shaft... It's kinda a "duh" result. These trucks are powerful. It's easy to forget how much stress is put on components when you set your programmer to kill and the stereo to loud.
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jaber
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Re: '75 J-20 service truck

Post by jaber »

Sooo, what are you sayin bout me... :D :D :D :evil:
Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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tedlovesjeeps71
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Re: '75 J-20 service truck

Post by tedlovesjeeps71 »

jaber wrote:Sooo, what are you sayin bout me... :D :D :D :evil:
Turn it up and get crunked! ImageImageImage
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jaber
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Re: '75 J-20 service truck

Post by jaber »

I guess i just feel that the ujoints should be the weakest link, like in old school trucks...
I'll be watching for parts, got a couple friends in the tow business. I have a couple other builds I need to do before I get too excited with this one. It's doing it's job better then I thought and that makes it all worth it. Getting to know it well enough to float the gears, helping to make the clutch last longer. Just rolled 261k...
Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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jaber
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Re: '75 J-20 service truck

Post by jaber »

Well, I guess I should give an update.
12 months as of Xmas eve and she is still going strong as my DD. I have just over 10k miles on her and the hydroboost is starting to leak.
I bought myself a chinese double DIN touch screen stereo for it(told the wife it was for backup cam), but the Bluetooth don't work so I'm waiting on a replacement. The camera works... :banghead:
Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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jaber
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Re: '75 J-20 service truck

Post by jaber »

God I love my truck...ImageImageImage

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Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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Chubbinius
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Location: SD, CA

Re: '75 J-20 service truck

Post by Chubbinius »

jaber wrote: Tue Sep 10, 2019 2:54 pm God I love my truck...
Nice! That Service Truck rocks! :-bd
1970 1414X Wagoneer "The Pig"
-Custom Special
-Dauntless 350 V8
-D27 front/D44 rear
2006 XK (65th Ann Edition)-DD
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Topic author
jaber
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Re: '75 J-20 service truck

Post by jaber »

Found a group of wranglers and one of them had a flex ramp, so you KNOW I had to...ImageImageImage

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Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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Resbum
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Location: North East Oregon

Re: '75 J-20 service truck

Post by Resbum »

What a cool truck. Congrats.

Resbum
Originally Posted by Resbum
"What year is my truck?... Which part?" Build thread- http://www.fsjnetwork.com/forum/viewtop ... 290#p18290
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Topic author
jaber
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Re: '75 J-20 service truck

Post by jaber »

For the first time in 11 yrs of driving this truck, it finally has 4wd again.

I also put an all aluminum 3 core radiator, a boost fooler and adjustable boost elbow. I am finally feeling the 40 over injectors now.
Damn thing needs tires again...Image

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Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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Topic author
jaber
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Re: '75 J-20 service truck

Post by jaber »

Fed-ex just dropped off 4 new thunderer mud track tires in a 285 75 16 shoe size. :D
Should have them on soon, then its going to need ball joints. Not done anything major but fuel and drive. I did a pair of batteries from Costco a few months ago. I put an adjustable boost elbow, boost fooler, and boost guage in.
Put the front shaft in, when it snowed, it wouldn't engage the front axle. Pulled the vac cover off and manually engaged it. Pulled it apart on a dry day and the shaft on the vac shifter was seized, got it freed and working, hope it works next time.



She's almost to 285k and still running as well as when I started. Thats 30k miles in this configuration. I'm so pleased with the outcome, I have a wrecker buddy watching for a Hemi setup for the wife's Wagoneer.
Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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66stepside
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Re: '75 J-20 service truck

Post by 66stepside »

This build is one of my favorites- keep it going!!


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jaber
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Re: '75 J-20 service truck

Post by jaber »

Thank you. It has been fun. I still get guys following me into businesses just to look at it.
Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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Topic author
jaber
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Re: '75 J-20 service truck

Post by jaber »

Got them all mounted, just waiting on lugnuts to mount them. Does anyone recognize what rims these are?

Image
Image
Image

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Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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Topic author
jaber
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Posts: 3066
Joined: Sat Aug 27, 2011 5:24 pm
Location: Chino Valley, Az.

Re: '75 J-20 service truck

Post by jaber »

Ok, got lug nuts and got time to mount them. I'm liking the look.ImageImage

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Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/
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