New (to me) 1st gen dodge cummins build

[de5id]

Well thought I'd post a few pics and introduce my new truck. It's a 92 le cummins 4x4, picked it up in Mass last week for a daily driver/ father son/ expo truck project. Before this I had an 89 wrangler with a mercedes diesel that worked great but didn't have the room I was looking for extended camping and back woods road tripping. This truck is pretty solid no rust (Texas truck) and good motor. I plan on keeping the drivetrain as stock as possible for reliability and dependability. This will probably be a slow build but I plan on being finished in the next two years before my son starts driving. Right now I'm chasing down some gremlins with the speedo/wiring when that's done I'll move along to the maintenance and that's about as far as I've planned so far...

So here it is and if anyone knows anything about these first gen dodge speedometers and their wiring/components pleas let me know

-matt

 

[gahi]

cool, good looking truck.

For the speedo, check the sending unit on the transfer case. Pull off the connection and clean the contacts. If its an auto trans it wont shift into OD without the speedo signal.

 

[DoMiNiC1]

Great truck, truck will go before the motor does!

 

[Warn Industries]

Always been a fan of the first-gen Dodges.

- Andy

 

[Revco]

cool, good looking truck.

For the speedo, check the sending unit on the transfer case. Pull off the connection and clean the contacts. If its an auto trans it wont shift into OD without the speedo signal.

If the electrical connection on the "sending unit" or VSS (Vehicle Speed Sensor) is okay, then the problem could be within the VSS itself. I went through alot of trouble with the VSS on my old '92. I eventually just gauged my speed by the tachometer and dreamed that my cruise control would work without the VSS. I've also heard of the speedo itself being troublesome, but that was a more rare problem.

Even though it was a Texas truck, watch for rust on the roof as it's very common on these trucks. If that visor is fastened to the roof, you should take it off to access the mounting holes and spray a rustproof coating into the roof through those holes. Also go through the inside visor holes.

These trucks have a problem with the cowl sides cracking. Dodge even has a TSB for it, but being 20 yrs old now, I don't know if they have the repair parts available. If you hear metal-on-metal squeaking, or have water on the floorboards after a rain, you most likely have the cracked cowl. It's a weak point in the cab design that cracks under movement. Not a big deal, and an easy fix once you remove the fenders.

You can do some free tweaks to the VE injector pump to gain some more power, and a simple swap to a 2nd gen HX35 turbocharger will also help, but none of those mods would be worthwhile without putting a larger exhaust on it and a bigger air filter. I always used the big BHAF air filters and 4" straight pipes on my Dodges. My old '92 was a 2wd 5spd reg cab that made 342hp/841lbft and was my daily driver that got 26mpg on the highway and about 19mpg pulling my loaded car hauler. I built that truck up on a budget and did everything myself. It had a HX35/40 Hybrid Turbo, tweaked pump, Old Smokey Fuel Pin, 4" Single Exhaust, BHAF, and POD Injectors. It was the 2nd most reliable vehicle I ever owned, right behind my old '97 Dodge Cummins.

Sorry for the long reply, these old Dodges get my blood pumping.

 

[de5id]

I really appreciate the help it's more than anyone's offered on other forums... The problem I'm running into with the speedo is the vss was missing all together and I can't seem to find the connectors either. And the tps has already been disconnected and wired to a switch on the dash for the od. I bought a tps delete kit for the od for a permanent fix and a vss hoping maybe i can get enough of it together to make it work. the speed sensor for the abs is there. I just gotta figure this out soon so I can get the truck registered here in va.

Thanks again

 

[de5id]

Heres a couple pics of what I'm working with

 

[Revco]

The TPS is another fluke on that era. Most times when the TPS acts up it just needs the contacts to be cleaned up and it will work fine. Seems like the previous owner didn't have the patience to do it right and hard wired it to a switch. No telling with the missing VSS wires, they may be tucked up over the transmission or something.

Another thing to watch out for is the tensioner pulley. It's plastic and can wear unevenly, forcing the serpentine belt to slip grooves enough to eventually come loose. Mine went through several belts and eventually chewed the crank position sensor wires up before I found the culprit. At that time the only pulleys available were also plastic, so I machined a new one from billet aluminum and never had another problem with it.

I usually disconnect the ABS on my vehicles as I'd rather be in control of it. If you spend any time driving that truck on gravel roads, you'll want to ditch the ABS as well. With that stout suspension, even the slightest traction loss while braking will engage the ABS, which becomes more dangerous than not having it at all. It's as simple as disconnecting the ABS control module behind the glove box.

The throttle shaft is also another common thing to wear out, along with the return/tension springs. You can get those at your local Bosch or Cummins dealer.

Probably the single best upgrade to a stock truck is swapping out the 21cm turbocharger exhaust housing with a smaller 12/14/or16cm housing. Improved throttle response and a major decrease in boost lag can be had by just swapping out that one single part. I think I have a 12cm housing laying around somewhere, and if I can find it, you can have it for $20 shipped, since I'm a nice guy.:sombrero:

Of course with any modifications, you'll need aftermarket gauges. EGT and Transmission Temp are the most important, Boost gauge is fun, but it's not as critical as monitoring the Exhaust and Trans temperatures.

There's tons of info out there on these trucks. One of the best resources is www.dodgeram.org . Lots of great tech info there. There's also dieseltruckresource.com, turbodieselregister.com, and dieselbombers.com

 

[pulltilbroke]

From the pics you posted your missing most of the ratio adapter and the VSS.

1stgen.org is also a good site.


Gimme a few minutes and I'll go snap a pic of what your speedo setup should look like.

 

[pulltilbroke]

Heres what it should look like

 

[de5id]

That's what I was afraid of... I found a site that sells the ratio adapter I'll have to get that ordered tomorrow. I'll post some more pics as the progress goes along thanks for the pics it's been impossible trying to track this stuff down when you don't know what your looking for

 

[de5id]

In The mean time Here's a couple more pics from the add last one
Is my son with "his" new truck after getting it home

 

[Revco]

Yes, the damned ratio adapter, thats the bastard part I had troubles with. I screwed the VSS straight into the transmission and bypassed the adapter. The speedo worked, but bounced everywhere. The shaft inside the adapter was worn, so I had a truck shop repair it for $50, that worked for about 3 days, so they replaced it for another one that last about a month, then I finally broke down and got one from Dodge for about $80. It's gear ratio-specific, so it's supposed to match the rear axle ratio. I sold my '92 in '05 and miss it everyday, but not as much as I miss my '97.

 

[TheAlmightySam]

^ yup, those damn ratio adaptors - I'm rollin' without one these days too :sombrero:

Looks like a nice clean truck! Looking forward to the build!

 

[de5id]

I'm still debating on buying one for 89$ from PATC or the universal pickup and speedo signal box from Dakota digital for 119$ the thing with the Dakota digital setup is its programmable for different size tires and gears....what to do....