Roosterman17

I'm having some gearbox (I think) issues with my 2006 GL500. It's fine for short trips, but if I've been driving on steep, windy mountain roads, the gearchange starts to get very jerky, even banging to the point where the whole vehicle shakes. It also gets stuck in gear and won't change. e.g. when I got to the top of a steep mountain road it wouldn't change up out of second gear, even though it was revving up to 5,000 rpm. I tried slowing down and speeding up, and tried changing gears manually using the buttons on the steering wheel, but it didn't make any difference. Eventually I pulled over and turned the engine off and waited a few minutes, and it seemed a bit better after that, and I was able to get home. I've also had problems after coming off the motorway after an hour or so of driving at 110 km/h. It's fine whilst on the motorway, but after I turn off I have the same problem with banging gearchanges, and getting stuck in gear. I've also had an almost total lack of drive after coming off the motorway and stopping at traffic lights on a hill. When the lights changed I accelerated but the vehicle hardly moved. The engine revved but the vehicle slowly crawled up the hill. I took it to the garage, and they reset all the fault codes, and it seemed to be ok after that for a few weeks, but the same thing happened again yesterday.

Has anyone had any similar experiences or any thoughts on what this might be?

Thanks

Max Blast

Speed sensor failure on the valve body locking the tranny in 2nd gear, limp home mode.

mileage and service history of tranny please?

Roosterman17

Thanks. Mileage is 156,000 km. I don't know the full service history as I only bought it 2 months ago.

Max Blast

Have it scanned with an MB compatible tool and look for codes, stored or preferably current relating to the y3/n8 (iirc?) vehicle speed sensor.

if stored you had an event that triggered the symptoms you described. Your mileage is low enough to that this could be intermittently caused by dirty trans fluid, so you may get away with a full flush. At only 90k miles that’s a fair assessment, even if the trans has no service history.

if the code is current well then there’s your problem. Might be able to flush and reset the code, otherwise you’ll need a new VSS mated to your valve body. That’s a dealer only ($$$) or third party mail in ($) process.

Haytham

I would first try check the trans oil. While youre under the hood you should check your radiator's general condition too because it cools the trans fluid, if its old you might be mixing coolant into your trans fluid which really screws with your gear clutches. You can check the coolant reservoir for signs of oil contamination as well.

But in anycase i would advise a transmission flush, new oil and filter like the gentelmen mentioned in the prior reply. Good luck.

eric_in_sd

Reminder that when the transmission has an unknown history, or is experiencing problems, a tranny fluid change (drop pan, change filter, clean pan, refill approx 5 qts) is recommended rather than a flush. The full flush can dislodge so much gunk that it overwhelms the filter or something. Better to just change half the fluid and change half again in another 40k miles / 70kkm.

Of course, if a bunch of metal drops out when you drop the pan, don't even bother putting in new fluid. Or put in used motor oil and cat urine, and sell the thing.

Roosterman17

Thanks all, I'll try a fluid change to start with.

Here's a pic of my GL 500 with a new roof rack for the spare wheel. Works well but makes a lot of noise on the highway - I think it's actually the straps that make the noise rather than the wheel & tyre. Any suggestions for how to reduce the noise?
Thanks,


new roof rack for spare wheel

eric_in_sd

Just move it toward the rear. You can see the air flowing over the windshield hits the tire, wham.

You also can route the strap (really you only need one) differently. Try going under the tire, up through the wheel spokes, back down through the spokes, and under the tire to the other side. Or have one strap going front to rear, not side to side.

Looks sharp, though. I love seeing these Gelandewagen in their natural environment.

Wait - you're in Oz?!? You ever have any problems with killer koalas jumping on your truck, trying to fight their way in? Aren't they called drop-bears?

Roosterman17

Luckily drop bears are very reclusive, and only seem to attack tourists...

Max Blast

Any resolution or valve body/speed sensor related codes on this?