Hot gearbox

[MarkSP]

Hi all.

I took a 500 km trip with my BJ73. After 200 lm aprox I noticed that heat was coming from the tranny tunnel. I could feel the gearstick hot to the touch. Not scorching, but definitelly hot. I also could feel the cabin floor over the tranny quite warm.
After reachin my destination and parking the car, I touched the gearbox and it was hot. It will burn my hand within a few seconds.

The shift was normal, no strange noises or difficulties whenever I needed to shift gears.
But it was very hot inside, more that in my opinion it should.

The car has a 12HT on it. The trip was 100% highway and the speed was around 95-105 kph during most of the time., with RPMs around 2200-2400

I wonder if this is normal. Otherwise, what could be the cause for this?
May be the gearbox is low on oil ?

Thanks in advance.

 

[sodafeld1]

Most certainly check your oil levels! Both gearbox and transfer. I assume you have a h55f gear box. The seal between gearbox and transfer can give way and either most gear oil goes to your transfer, or apparently sometimes vice versa.
Some put a hose which acts as a bypass from the oil fill of transfer to gearbox oil fill, it equalises the oil level. Some don't like this idea and only recommend as a temporary fix and say to get at the transfer seal asap. Could also be a blocked vent outlet from the transfer.

I have experienced my h55f gear box hot , not sure as hot as you, when I towed a heavy load for over 200km during a 40c day. I checked my transfer oil filler and gear oil poured out, my gear box was nearly empty! I put one of the bypass hoses on 4 years ago, it is happy since even when towing.
I will do the gearbox/transfer seal when I replace my clutch, rear main oil seal, sump pan seal and throwout bearing at the same time.

Perhaps that is what it is. Check your oil levels in both gear box and transfer. If one is full the other empty, probably most likely the seal.

 

[mudgudgeon]

As above, check oil level is the first step.

When was the oil last changed? Would be a good idea to drain, check the oil is clean and free of metal debris.

What's the ambient air temperature like where you are at now? Spain? Mid summer?

I would expect gearbox, diffs engine all to be to hot to put your hand on after 500 km road trip

A 500km trip at highway speed means everything is going to get heat soaked.
All the exhaust heat passes by the gear box. Engine heat flows down the transmission tunnel, and heat from normal friction in the gear box will all contribute to heat soaking gear box, floor, diffs etc

It's normal for floor and gearbox to get hot on a long trip. It's something that is often commented about with HDJ80 owners. An 80 series has better floor insulation than a 70 series.
My feet used to get hot in my hdj80 doing road trips. The exhaust passes under the drivers feet. And I'd feel heat coming through the floor around the gear stick.
I added insulation to the floor, and around the shifter and it reduced heat in the cab a lot.

 

[veiloctane]

Heat shields still in place?

 

[Gimme a 60]

I’m sure it’s normal.

On long highway drives my BJ60 gearbox shifter gets hot too.

 

[MarkSP]

Thanks all for your messages. I will take the car to the mechanic to check whats's going on

Heat shields still in place?

I do not think thtat this car has such thing over the gear box.

 

[bj70bc]

change the oil
it will tell you things