Getting through the firewall on the 3rd gen

[Matt400]

I'm installing a SPA dual gauge and already have it in the SRT-10 A Pillar but have a question...

I have the interior gauge & wiring plus the exterior probe stuff all worked out and am looking for a slick way to get through the fire wall.



If it was just the wire it would be no biggie but the SPA gauge I chose has a 3/8" wide connector for the trans temp and the EGT is a 3/4" flat connector so some big holes are in order.



If I were to feed the EGT thermocouple through first that would reduce the needed size down to 3/8" but I also want to make probe changes a snap.



Anyone find a slick spot for getting wires with connectors on the ends through the wall?

 

[AndyMan]

Eeek. . I don't have anything creative to offer you, but I can tell you what I did. Since I have the 48RE, There is a thick plastic plate bolted to the lower firewall where the clutch assembly would pass through. I unbolted it (2 bolts), drilled the holes I needed, ran my lines, then bolted it back up. Since you can actually work with the part away from the truck, it may permit you some liberty that you would not have working on your back in the floorboard.



Hope that helps!

Andy

 

[Crunch]

Originally posted by Matt400

I'm installing a SPA dual gauge and already have it in the SRT-10 A Pillar but have a question...

I have the interior gauge & wiring plus the exterior probe stuff all worked out and am looking for a slick way to get through the fire wall.

AndyMan beat me to it, but I did the same thing, except that I didn't unbolt the plate before drilling it. The nice thing about using the plate is that it is A) a replacable part and B) easy to seal with silicon. I drilled a . 5" hole in the center circle to run the coax for my CB antenna. I used a hollow rubber plug with a flange on it to firm up the cable and sealed it with silicon on the engine side and the cab side. Haven't had any problems and I can yank out the coax at any time without trashing anything.



I didn't know what else the bolts fastend so I didn't remove them. But AndyMan is on the right track by pulling it off. Once you have the plate on a bench you can drill several holes of various diameters and/or angles to run cable through, or one large hole for a wire bundle. The clutch assembly plate is definitely the way to go for an automatic. You can easily inspect and access the cables from the engine or cab side, and that alone makes it worthwhile. The guy that tuned my CB antenna thought I was nuts at first (he wanted to run the coax up through the floor board and along the molding) but was impressed when the job was finished. If you're a perfectionist you could fabricate a loom or harness that fits the plate and use quick connectors for a real professional-looking install.

 

[Matt400]

Just so happens I do have an auto so that will work out real well however I will be doing a friends 6 speed also.

Hrmm I bet the 6 speed will have the auto trans shift cable hole available??



Thanks for the info!

 

[nickleinonen]

i was looking up under the dash a few nights ago, and there is a plug below the clutch pedal that should go through into the engine compartment, but it sits pretty low down, so it could be kicked [it is below and left of the clutch, just above where the carpet ends]

 

[banshee]

On my 6 speed I used the plug below the clutch. The plug itself has a long finger that sticks into the engine bay... not sure why. I cut the center out of it and then ran the wires through it. Since the hole is pretty big I plugged it with a plug I made to keep out dirt, water, and noise. So far so good.



John

 

[klenger]

Here's how I ran the wires for my BrakeSmart controller thru the firewall.



http://www.klenger.net/dodge/brakesmart/slide02.html

 

[Matt400]

Originally posted by klenger

Here's how I ran the wires for my BrakeSmart controller thru the firewall.



http://www.klenger.net/dodge/brakesmart/slide02.html

Thanks for that slide show, real nice install. The trailer co. installed my control when I bought the trailer and put it over the knee bolster mounting screw on the right.



Location is ok except that every-time I want to pull the bolster I have to take off the controller.



About that brake smart... why do wires go through the firewall?

I have a Tekonsha Voyager cuz its what they supplied with the trailer- seems to work ok but as far as brake controls is this a standard unit vs your brake smart?

 

[Matt400]

nickleinonen & banshee-



Yes I see that plug, on mine its where the transmission shift cable goes through. . thanks for the info!

 

[Buffalo]

KLENGER, Thank you, for all the information You pass on to us. You go to a lot of effort to make sure the information is very clear and understandable, to us, with Your use of pictures, slide shows, etc. I,ve used your suggestions a number of times and always look forward to your posts. Thank You, again. Joe Fihn.

 

[Buzzer]

Originally posted by Buffalo

KLENGER, Thank you, for all the information You pass on to us. You go to a lot of effort to make sure the information is very clear and understandable, to us, with Your use of pictures, slide shows, etc. I,ve used your suggestions a number of times and always look forward to your posts. Thank You, again. Joe Fihn.

I agree. Thank you!!

 

[Jengle]

I used the plug behind the clutch pedal to route my gauge wiring through. I just tie wrapped them tight to the side, so the clutch pedal won't hit them. The long thing that someone mentioned, I cut off and made a small hole in the center of the rubber plug, then sealed the opening with black silicone sealer. It's rubber sealant, so I can remove it, if I need to.

 

[klenger]

The BrakeSmart has wires that go through the firewall because it uses a hydraulic sensor to sense brake pressure and then outputs an electronic signal to the trailer proportional to the brake pressure. The pressure sensor is mounted to the brake assembly forward of the firewall. See pics at http://www.klenger.net/dodge/brakesmart/slide01.html



Thanks for the very kind comments. One of my goals is to gather info for topics that come up on the fourms and post it on my website. I figure if the same question gets asked 6 times, it might be of general interest. I try to stick to subjects that I understand, which is why you will see topics having to do with towing and RV's and instead of engine bombing. I have been known to also put stuff on my website contributed by other members, like 3rd gen power mirrors on a 2nd gen truck.

 

[Matt400]

Originally posted by klenger

The BrakeSmart has wires that go through the firewall because it uses a hydraulic sensor to sense brake pressure

That is slick! I like the pressure sensing method vs my set up.



I found this post with allot of good info.



Dang... Coulda had EGT/Boost gauge too.



I just installed a SPA EGT/Trans Temp dual gauge in the SRT-10 A pillar but was bummed to not have boost. I didn't care for the X monitors look. I coulda put a trans temp gauge there and bought a new brake smart for all 3 but I do have to admit the SPA is a nice gauge with lots of neat features in the menu's.



I'm gonna keep an eye on this one as it would allow me to have a boost monitor while upgrading the controller. Thanks for all the info

 

[klenger]

The BrakeSmart boost and EGT functions are not available yet. I asked last week, and the only reply I got was "soon".

 

[Duck]

Originally posted by klenger

Here's how I ran the wires for my BrakeSmart controller thru the firewall.



http://www.klenger.net/dodge/brakesmart/slide02.html

Man, all I can think of is, "How in the heck did you take that picture?!?"

Pretty tight squeeze to get a camera in there. I was just feeding wires through that grommet tonight, so I should know