transfer case bumpin the aux fuel tank

[m4r1u5]

Hi guys,

when I drive my dual fuel (unleaded & gas) Patrol GQ offroad or over bumps, I think the transfer case or the rear trailin arm is hitting the aux fuel tank, which makes a sound of a metal sheet popping in and out - which is really annoying.

Is that a common problem for dual fuel Patrols?
Can something break or suffer from it? How bad is it?
And most important of course, can it be fixed somehow? (How much would it cost?)

Thank you and cheers, Marius

[JackCollo]

Have you had a look under neath the truck to see where it might be fouling on the tank.
It might help to know what it's actually hitting on but I wouldn't say it's the transfer case.

Let me know how you go

[happygu]

There are aftermarket bent upper trailing arms to clear 75 Litre Aux Tanks, so yours might be this problem. This is where I would be looking first.

[threedogs]

Could be your tail shaft fouling as well over bumps, I ve seen that happen a lot

[kbchez]

I have the same problem. I have been trying to work out what it is. Must check it out. Next time I put it in my shed.

[my third 256]

hi and welcome to the forum a great mob of people here and a lot of very usefull information
best wishes with your patrolling
stephen

Jump over to the intros and say g'day mate something we ask all members to do, cheers, you'll get a better response that way http://www.nissanpatrol.com.au/forums/forumdisplay.php?2-Introductions

[dom14]

Hi guys,

when I drive my dual fuel (unleaded & gas) Patrol GQ offroad or over bumps, I think the transfer case or the rear trailin arm is hitting the aux fuel tank, which makes a sound of a metal sheet popping in and out - which is really annoying.

Is that a common problem for dual fuel Patrols?
Can something break or suffer from it? How bad is it?
And most important of course, can it be fixed somehow? (How much would it cost?)

Thank you and cheers, Marius

Speaking from the experience crawling under mine(RB30 with long range tank behind the transfer case, next to the tail shaft).
That's where the original auxiliary tank used to be, I think, and where the rear main tank used to be has the LPG tank now(dual fuel).
So, I don't see how it's possible for the petrol tank to grind on transfer case.
Tail shaft is pretty close to the tank(about a centimeter) in my case, but I still don't see how it's possible for the two to grind on each other, unless the tank has become loose, in which case it is dangerous.

If you think it's auxiliary fuel tank that's getting hit by something, they you can most certainly see some marks on the tank.
A good place to start fixing it.

[m4r1u5]

After I checked the problem another few days, I must say it feels like something is pushing in the fuel tank (maybe from inside or above) and it doesn't sound like something is really hitting the tank. (couldn't find any marks)

Two major things I noticed:
- If the tank is completely full the sound of the popping metal sheet doesn't come up. The less petrol is inside the tank, the more this noise comes up
- If there is a person sitting in the back seat, the noise comes up more quickly.

Any ideas with my new discoveries?

Thank you and I will upload photos later.

[dom14]

After I checked the problem another few days, I must say it feels like something is pushing in the fuel tank (maybe from inside or above) and it doesn't sound like something is really hitting the tank. (couldn't find any marks)

Two major things I noticed:
- If the tank is completely full the sound of the popping metal sheet doesn't come up. The less petrol is inside the tank, the more this noise comes up

Sounds like it's coming from inside the tank. I'm wondering whether the intank strainer/filter has dislodged and moving inside the tank, making that noise. Or the tank might have come loose?! Full tank means more weight and the tank may be not moving due to weight?!

Either way, this is not something you wanna put off. Sooner you find out the reason, the better it will be for your health.


If there is a person sitting in the back seat, the noise comes up more quickly.

Any ideas with my new discoveries?

Thank you and I will upload photos later.

I am not sure how to interpret that. My guess would be it isn't related to somebody sitting on the back seat.
But having said that, anything's possible. If there are modifications to the tank where the holding bracket has a bolt going through the floor and then to the seat mount(which might have come loose).

Yank the seat, tank, etc and find out what's causing it.

[threedogs]

Ill still say the exhaust is hitting the cross member, pretty common fault.
Chock the wheels get under and have a very good look with a torch
I mean't to say the tail shaft hitting the cross memmber, marks should
be very easy to see

[kbchez]

I had the problem when going over judder bars quickly sounded like a empty tin can. I have fitted a winch. Now that problem has gone.
Maybe the shocks are worn and allowing to much movement in the coil spring department. The heavy winch holding the body down .. food for thought.

[Lightspeed]

Like happy gu said you may need to fit a right hand bent upper control arm. They are made for patrols with aux fuel tanks for off-road use. I have fitted two on mine but only one is really needed.