Transmission Switch query (1 Viewer)

[CanuckMariner]

Noob query? I have a '91 PZJ77 with e-hubs. There is a set of switch lower right near steering wheel. One is Hub lock and one is H4. Which order are they to be switched? i am think Hub lock first then H4.

next query: why have two switches? is there an advantage/purpose to switching one and not the other? Why have hub locked but not in 4WD? why in 4WD with out hub locked?

 

[Mark_kzj78]

Noob query? I have a '91 PZJ77 with e-hubs. There is a set of switch lower right near steering wheel. One is Hub lock and one is H4. Which order are they to be switched? i am think Hub lock first then H4.

next query: why have two switches? is there an advantage/purpose to switching one and not the other? Why have hub locked but not in 4WD? why in 4WD with out hub locked?

Yes to your 1st question - Lock the hubs first (must be done with vehicle stationary or less than 5mph) then engage 4WD.
Advantage of two switches is that you can drive around with your hubs locked and then engage 4WD when you need to while you are still at speed. The 'supposed' advantage of being able to disengage the hub locks is that you aren't wearing the front diff. components and half shafts etc. Oh and better fuel economy. You can't engage 4WD without locking the hubs - it won't let you.

Regards
Mark

 

[CanuckMariner]

Yes to your 1st question - Lock the hubs first (must be done with vehicle stationary or less than 5mph) then engage 4WD.
Advantage of two switches is that you can drive around with your hubs locked and then engage 4WD when you need to while you are still at speed. The 'supposed' advantage of being able to disengage the hub locks is that you aren't wearing the front diff. components and half shafts etc. Oh and better fuel economy. You can't engage 4WD without locking the hubs - it won't let you.

Regards
Mark

Thanks Mark, thought as much, but just wanted to make sure. I gather that putting it in H4 at speed with the hubs already locked, will not damage anything?

 

[crushers]

once the hobs are locked you can engage 4H at any speed EXCEPT going around a corner is not advised.
when turning all 4 tires are rotating at different speeds.

 

[Mark_kzj78]

once the hobs are locked you can engage 4H at any speed EXCEPT going around a corner is not advised.
when turning all 4 tires are rotating at different speeds.

as crushers said... ideally you want to have the wheels straight and just let off the gas a touch so that the drive train isn't loaded at the moment of engagement. Off course if your are heading out of control and need the 4WD i'd engage it at any time...the system is robust enough to endure that occasionally I think.

 

[gotoy]

I have both the switches on my lj70.

The auto hubs were removed and the manual locking one kept on when the half cut was installed. So now the hub lock switch is not used.

When offroad I will lock the manual hubs then I just switch on the 4wd button as and when needed. When 4x4 is not needed I'll unlock the manual hubs.

I only switch when either stationary or at very low speeds <5km/hr.

 

[Mark_kzj78]

I only switch when either stationary or at very low speeds <5km/hr.

be hard to switch to manual lock when you are moving... (just kidding - I know what you meant)

toyota manual says that you can engage 4WD high (once the hubs are locked) whenever and does NOT say you need to be stationary or slow. that only applies to engaging the hub locks - just so people know!

 

[crushers]

for hub lock and engaging 4 low you should be stopped.

i tell my customers that if you try it at speed you will hear this cool grinding noise ... kinda like burning money.

 

[gotoy]

for hub lock and engaging 4 low you should be stopped.

i tell my customers that if you try it at speed you will hear this cool grinding noise ... kinda like burning money.

Yes correct. I only push the 4wd button, to engage or disengage, when stationary...although in rare cases I do it at slow speed < 5km/hr.

 

[CanuckMariner]

Thanks, guys! Clears this up for me. I have been doing both switches only when stopped, now I know I have a bit of leeway.


On another related query, where can I get the little 24V bulbs that go in these switches? Toyota dealership says they are for a forklift and they need the VIN to order. 4WheelAuto sent me bulbs that were way too big. G&S doesn't have any. Anyone know who does have some, I need two.

 

[crushers]

if you are in calgary then try ...what the hell was it called ... Greggs south on 52nd st and just north of 71 st ave, they had them in stock when i was last there...

 

[CanuckMariner]

if you are in calgary then try ...what the hell was it called ... Greggs south on 52nd st and just north of 71 st ave, they had them in stock when i was last there...

Thanks Wayne, will them a try!

 

[drfvdr]

Just as an addition, shifting to 4wd Hi while driving is all good BUT make sure that all of your tires are of similar rolling diametre ie. not new on back and worn on front or vice versa

 

[CanuckMariner]

Just as an addition, shifting to 4wd Hi while driving is all good BUT make sure that all of your tires are of similar rolling diametre ie. not new on back and worn on front or vice versa

Not an issue with my situation, but thanks anyway.

 

[cicak]

I have both the switches on my lj70.

The auto hubs were removed and the manual locking one kept on when the half cut was installed. So now the hub lock switch is not used.

When offroad I will lock the manual hubs then I just switch on the 4wd button as and when needed. When 4x4 is not needed I'll unlock the manual hubs.

I only switch when either stationary or at very low speeds <5km/hr.

I have the sme setup and have to press the HUBS button first else the H4 button does not work - we both go to the same mekanik so I must ask him tomorrow when I pay a flying visit to check the Volvo (Thunderbird 2) which is still sitting in Hangar 1 as the portals with the disc brake brackets are due back this week.

 

[gotoy]

I have the sme setup and have to press the HUBS button first else the H4 button does not work - we both go to the same mekanik so I must ask him tomorrow when I pay a flying visit to check the Volvo (Thunderbird 2) which is still sitting in Hangar 1 as the portals with the disc brake brackets are due back this week.

My lc is at the mekanik place too. The front hub is jammed so with the manual wheel lock in 'free' or 'lock' the shafts still rotate. ...funny cos I never come across this before. Awaiting a price from him on changing the winch arrangment.

As for the switches, yes you are probably correct, I have the habit of pressing both switches in. However if the wiring was changed slightly, the hub switch button would make a useful spare for something else.

 

[CanuckMariner]

if you are in calgary then try ...what the hell was it called ... Greggs south on 52nd st and just north of 71 st ave, they had them in stock when i was last there...

Greggs doesn't have them.

Any other ideas from anyone?