My kid wanted a Jeep, she's getting a 77 FJ40 LS Swap instead

[thatcabledude]

Looks like it’s too late now, but I would have swapped the knock sensors while you had the intake off. Based on the foam blocks still being there and that debris, I bet they’re real good and crusty down in their holes.

There’s a TSB of sorts from GM which advises removing the foam blocks and RTVing the rubber knock sensor covers to prevent corrosion. They also say to build a little RTV dam around the hole. Supposed to keep moisture out of the cavity.

This video kinda covers it:

 

[JKIII FJ40]

Thanks, it’s a gen IV so no knock sensors under the intake.

 

[thatcabledude]

Thanks, it’s a gen IV so no knock sensors under the intake.

Doh, I was so zero’d in on the mouse nest that I didn’t notice the 4+ obvious indicators of that

 

[fireflyr]

The pigtail Dakota Digital sent unwound itself in about 1000 miles (acted just like a bad speedo cable bouncing around) so I just switched inputs to the VHX Control Box (green white wire) from the BP Automotive harness. It picks up its signal from the interrupter on the shaft extension. Can’t remember which transmission you have, but I have a 4L60e. I remember the ground for everything was pretty important and I used the 5.3 block. I grounded the tub, frame and battery to the driver’s side rear of the block.

 

[fireflyr]

The DD GSS-3000 Universal gearshift sender was what I went with to display the gear in the display. It can display constantly or just when you shift. Might not be a bad investment for a new driver. Now that my knock sensors are disabled I can drive it in DRIVE rather than OD. It can’t be good lugging that thing around in OD all the time.

 

[JKIII FJ40]

no wor

Doh, I was so zero’d in on the mouse nest that I didn’t notice the 4+ obvious indicators of that

no worries, always appreciate a second look. I am far from a paid expert and twice isnt nice but I sometimes dont get it right the first time.

 

[JKIII FJ40]

The pigtail Dakota Digital sent unwound itself in about 1000 miles (acted just like a bad speedo cable bouncing around) so I just switched inputs to the VHX Control Box (green white wire) from the BP Automotive harness. It picks up its signal from the interrupter on the shaft extension. Can’t remember which transmission you have, but I have a 4L60e. I remember the ground for everything was pretty important and I used the 5.3 block. I grounded the tub, frame and battery to the driver’s side rear of the block. View attachment 4146667View attachment 4146672View attachment 4146679

thanks for the info. Before I switched mine over it was doing the same thing as you described. The green and white wire from the ECU is now dead on.

 

[JKIII FJ40]

The DD GSS-3000 Universal gearshift sender was what I went with to display the gear in the display. It can display constantly or just when you shift. Might not be a bad investment for a new driver. Now that my knock sensors are disabled I can drive it in DRIVE rather than OD. It can’t be good lugging that thing around in OD all the time.

View attachment 4146704

Thanks for the info. I was holding off as the BIM module was supposed to do that but didnt. I guess when I send the BIM back I can afford to buy one....

 

[JKIII FJ40]

Let the kid drive it tonight to get gas, after refueling the truck had an awful squeal. I first thought the fuel pump was going out, then when we got home the sound was coming from the fan. So I ripped it back down and thought I was going to reinstall the old fan motor (1300 CFM) as it sounded like the bearing went in the new (1600 CFM) fan motor. After getting it out I noticed the fan blade was slipping on the shaft. I got some washers and shimmed it out so there was no play on the shaft and tested it, all GTG. Grabbed the kid and let her take it for a spin, aside from being bouncy she didnt seem to have any issues. I need to get the springs to break in so it will ride better. I also need to get the tune checked as the shift points seem off and the engine fan comes on early. Work for another day. At least its drive able.

 

[JKIII FJ40]

The pigtail Dakota Digital sent unwound itself in about 1000 miles (acted just like a bad speedo cable bouncing around) so I just switched inputs to the VHX Control Box (green white wire) from the BP Automotive harness. It picks up its signal from the interrupter on the shaft extension. Can’t remember which transmission you have, but I have a 4L60e. I remember the ground for everything was pretty important and I used the 5.3 block. I grounded the tub, frame and battery to the driver’s side rear of the block. View attachment 4146667View attachment 4146672View attachment 4146679

fireflyer, what are you using for a fan? mechanical or electric fan?

 

[fireflyr]

fireflyer, what are you using for a fan? mechanical or electric fan?

Electric. I’m running a Champion aluminum radiator so it was easier for me to order their electric fan / shroud combo rather than try to fab up the shroud myself. It keeps everything at about 208F no matter the outside air temperature. Biggest drawback is the noise. It is LOUD.

*Sealed single fan relay kit was from BP Automotive.

 

[JKIII FJ40]

Electric. I’m running a Champion aluminum radiator so it was easier for me to order their electric fan / shroud combo rather than try to fab up the shroud myself. It keeps everything at about 208F no matter the outside air temperature. Biggest drawback is the noise. It is LOUD. View attachment 4147041View attachment 4147042View attachment 4147043

Many thanks, I bought the same one from Champion. Unfortunately the fan was still too deep so I went with a shallower one. It was only a 1300 cfm so over the weekend I installed a 1600 one and havent run it enough to see the temp range difference. The new one is loud for sure. What temp do you have yours triggered to come on at, mine is coming on at 160-180. I need to go see the tuner to get it adjusted and my shift points as at 30-40 is constantly changing gears.
In hindsight I shouldve placed the motor back just a tad more.
Thanks again for sharing.

 

[fireflyr]

Many thanks, I bought the same one from Champion. Unfortunately the fan was still too deep so I went with a shallower one. It was only a 1300 cfm so over the weekend I installed a 1600 one and havent run it enough to see the temp range difference. The new one is loud for sure. What temp do you have yours triggered to come on at, mine is coming on at 160-180. I need to go see the tuner to get it adjusted and my shift points as at 30-40 is constantly changing gears.
In hindsight I shouldve placed the motor back just a tad more.
Thanks again for sharing.

Fan is pretty consistently coming on about 185F. It was coming on lower when I had a replacement temperature sender installed on the right side of the block. Replaced it with a new one from DD.

 

[fireflyr]

As to your comment on the shifting at 30 to 40, mine does the same when I keep it in Overdrive. I shift it down to Drive around town and on country roads to keep it from doing that. It is annoying (shifts into OD at about 37 mph).
On my last trip up north, I got 16 mpg on the freeway (70 mph in OD) pulling a loaded M100 trailer with a kayak on the roof, but it improved to 18 mpg when I slowed down to 45 to 55 (in drive) mph on the county roads.
Obviously an aerodynamic issue that will never get resolved .

 

[JKIII FJ40]

Thanks for all of the info. Totally forgot about the OD, will need to try that to see the difference.

 

[JKIII FJ40]

Started working on the hardtop. The Topnault sides needed massaging. I had to cut out the inner rail and re-tack it back in once I was able to get it to the right measurement. In the third pic you will see how much bondo that was on them, really wished they woudlve shipped them with e-coating only. The Hard top rail wasnt bad enough to replace, I patched all of the bad areas and sanded the top to remove the moss and algae.

 

[JKIII FJ40]

More hard top fun, the new CCOT windshield cap came in. I need to drill holes to test fit it. The hard top is starting to shape up.

I am researching options for the headliner. On my 74 I used Silas sound deadening material and Home Depot indoor/outdoor carpet, it worked well. I would love to find a spray in sound deadener that can be tinted or painted instead.

 

[JKIII FJ40]

Radiator fan misery. I decided to drive it in to work one day, all was well in the universe. The temp was perfect for the sides rolled up and the truck ran great. As I was pulling in to a parking spot I noticed a mist and some steam from the front, I stopped and checked and sure enough I had pin hole leak in the radiator. I ran it home and swapped vehicles. That evening I tore the radiator and shroud out to get a better look. I found the fan had disintegrated and popped a few holes in the radiator. Luckily the radiator shop is still in business, they had it back in a day or so and I put the radiator back in. Never a dull moment.

 

[peesalot]

Just my 2 cents, I have a 2001 6.0, using stock radiator, mechanical stock clutch fan, and a shroud we modified a bit, runs 195. IMO lose the electric and aluminum.

 

[clrussell]

Just my 2 cents, I have a 2001 6.0, using stock radiator, mechanical stock clutch fan, and a shroud we modified a bit, runs 195. IMO lose the electric and aluminum.

I agree and run the same setup. Zero issues.