ARRGHHHH... Stupid 4WD system` (1 Viewer)

[Slowerthanu]

So, I have an 89 FJ-62 and I cannot get the 4wd light to turn off after turning it on.

I have replaced the switch on the dash!

I have replaced the vacuum solenoids on the firewall!

Both are new factory toyota parts.

I am going to check at the t-case with a vacuum pump this weekend and I am going to trace the lines but other than that I dont know where else to look!

Does anyone have any suggestions?

I am about to convert to a mechanical setup like my always working 77 FJ-40 has.

BTW, vehicle is BONE stock and 4wd works awesome when engaged, just wont turn off!

TIA, Dan Tubbs

 

[jesterb]

I dont know whats causing it to not disengage, but to force it too, try switching the vacuum lines at the solenoid with the button depressed.

 

[hightide]

i had the same problem with my 89 fj62. the light was on when i bought it and would not go of. i "fixed" it by switching the vacuum hoses on the solenoid. now every time i want to 4by i have to switch the hoses back around, i was going to buy the solenoid but know that i hear your situation im not sure what to do. keep us posted and good luck!

 

[dd113]

Swap the hoses and see if that works. Then trace the hoses and pay special atention where they go into the hard lines under the firewall, pull and clean the switch. have you determined it is actually in 4WD or is the light just on? Will the ft shaft rotate or is it locked?

 

[KLF]

Ya, like David said, unlock the hubs, then reach under the truck and see if you can spin the front driveshaft by hand. If so, you're out of 4WD and you just have a simple electrical problem like maybe a failed switch on the transfer.

If the driveshaft won't spin by hannd, then yeah you're still in 4WD. I have used a MitiVac hand vacuum pump at the t-case to shift it back and forth. Try swapping the lines at the firewall just below the solenoids, give it a try.

But I agree, the 4WD switching system in the FJ62 has got to be one of the stupidest setups Toyota has ever pushed out of the factory.

 

[dd113]

"But I agree, the 4WD switching system in the FJ62 has got to be one of the stupidest setups Toyota has ever pushed out of the factory."


Not sure if I agree with that. It is the exact same system they used in the late 60s and early 70s with the addition of the solinoid box on the firewall. The early system also used vac to engage the case. If vac is lost on a early case it goes to 2wd while on a 62 case it stays in 4wd (provided it was in 4wd when vac is lost). Beter to default to locked than not.

The design of the system was to allow the new tard cruiser owner to engage 4wd while moving at a normal road speed for bad conditions. The vac has an advantage over direct shift in that with direct shift you will try to force the splines of the FWD to engage the main gear shaft while the vac shift will apply continious, slight pressure until it all lines up and it slips in 4wd.

I agree that the solinoids do go out eventually but I see very little wear on the ft drive gear as compared to 60 series and late 40 series. The most commn issue is the plunger in the vac engagement piston gets gummed up through lack of use.

Ever seen Quadratrack? Talk about FUBAR from the factory.

 

[overhanger]

Damn, Ken. You sell the truck in the afternoon and by nightfall you are condemning the engineering of the 62? You mini-truck guys are all alike! #2 as it is said on the 3FE list!
J/K of course.

 

[Slowerthanu]

Ok, I guess I need to explain.

I did switch the lines and it did shut off.

I have not verified as of late whether the 4wd is actually engaging or not but it work great less than 2 months ago.

I am going to disassemble the plunger this weekend.

I will update with any changes.

Thanks for all of the help and advice.

Dan

 

[hightide]

what do you use to clean the solenoid?

 

[Ming89FJ62]

With all the vacuum junk attached did the vacuum switch from solenoid to solenoid when you pressed the button? If it did then it's probably a failed vacuum diaphram on the TC. Also there's a switch on the TC that closes to illuminate the 4WD indicator so in effect you actually have two seperate electrical curcuits for 4WD - one switches the vacuum source the other illuminated the indicator. Check each one seprately - haven't heard of many diaphrams crapping out but you never know. Good luck.

Ming

 

[KLF]

"But I agree, the 4WD switching system in the FJ62 has got to be one of the stupidest setups Toyota has ever pushed out of the factory."


Not sure if I agree with that.

Oh, I don't have any problem with the vacuum shift mechanism, for the reasons you describe. It's the electrical part of the system that's screwed up. Why does the 2WD solenoid have to stay energized 100% of the time the truck is in 2WD? This is why we're seeing so many failures now, they're finally all giving up. It would seem that they could have added one more detection switch to the system so that as soon as the plunger is fully retracted to 2WD mode, the current to the solenoid could be cut. Kinda like how the e-lockers work.

Steve, I've hated and cursed the 2WD/4WD shifting mechanism on this truck since the day my first solenoid pack fried, a month after I bought it. Then I REALLY hated it when it burned out ANOTHER solenoid within a few months. I actually keep my 2WD solenoid disconnected now at the firewall until I need 4WD and want to switch it back.

 

[Slowerthanu]

Has anyone ever converted to a standard t-case lever?

 

[dd113]

Has anyone ever converted to a standard t-case lever?

Jut get a 60 seres nose cone and shifter linkage. The only hard part would be making a pivot pont on the A440F to mount the linkage to.

 

[Slowerthanu]

Hmmmm, I might just have to try that.

 

[hightide]

i just saw on the 3fe forum that the solenoid can be replaced with one from a toyota van. anyone know if its a 4wd fan or a 2wd? i think maybe a 4wd van, but never seen one. what do i know