Rewaco VW Transmission oil question

[Retepnikrap]

Hi
I have a VW 1800i Rewaco trike (2006), I was very lucky to find this genuine 2k mile trike and over the winter I have been going through it from top to bottom as it had been stood for a number of years. Anyway I got to changing the transmission oil and the exhaust collector box and truck pipes make it impossible to get to the gearbox oil drain screw without removing a ton of stuff which I would like to avoid.

I have used a vacuum pump to take out as much hypoid oil as possible, jacked up the rear of the trike as high as possible to move the oil closer to the fill hole which I was using to pump out the old oil. I have managed to get 2ltr of the 2.5ltrs of oil out of the gearbox, if I was to fill with new oil will this be OK? Just can't get all the old oil out..... Old oil looks in good shape only done 2k miles but has been in for 10 years.

thanks and sorry for the European measurements but not sure of the US Equivalent.

thank you

[peteg59]

Of course, as you are likely aware, the only real way to remove old oil & potential contaminates is to fully drain the gearcase.
In the scenario you detail, were you able to inspect the condition closely for particulates/contaminates?
I assume you didn't send a sample for laboratory analysis?

If your old oil looked fairly clean with nothing floating around in it or contaminated with water, you should be able to top off with fresh oil & ride. VW transaxles are fairly forgiving, especially if the old oil only had 2K on it & was not found with metal or other foreign matter in it...

[Doug D.]

If your old oil looked fairly clean with nothing floating around in it or contaminated with water, you should be able to top off with fresh oil & ride. VW transaxles are fairly forgiving, especially if the old oil only had 2K on it & was not found with metal or other foreign matter in it...

Ditto, took the words right outta my mouth. Congrats on the find, too! How 'bout some pics?

PEACE and ride safe!

[Retepnikrap]

Ditto, took the words right outta my mouth. Congrats on the find, too! How 'bout some pics?

PEACE and ride safe!

Thanks guys, thought I may be OK, going to try and get a bit more out before I top up, old oil in good condition so if I can get 85% new oil in I will be fairly happy. No pics worth posting yet but as soon as I get it back together again I'll post some. Thank you

[DeathBySnuSnu]

I wonder if rewaco has a spec on the oil.
I would think that if they were going to make it impossible to change that they would have put a synthetic oil in it.
I dont like mixing types of oil.
Ok with me to mix brands of the same spec/type oil.

Synthetic is good stuff, but everything needs to be in real good shape in there. Putting synthetic in a worn gear is just gonna make it sound worse. Film strength is high but film thickness is small. Just aggravates an already worn condition.
Got an excellent box? Go synthetic and it will stay that way near forever.

GL 5 dino is a better oil than GL 4....
BUT.
GL 5 is not required to pass the yellow metal corrosive test at all.
Most GL 5 IF tested would pass. But untested it is an unknown. If you put it in your VW trans you will probably be OK and maybe not. No way to know without the grade test.

GL 4 is a lower grade of oil, not hypoid. But it does pass the yellow metal test as it is required for it to be GL 4 spec.
VW specs GL 4. The ring is not hypoid and the trans has yellow metal parts.

I use a valvoline dino gear oil that has the combo rating GL 5 and GL 4. If the labeling is true and they are not falsifying documents that would mean that it passes all the test of 4 and 5.

[peteg59]

Synthetic vs dino, syn wins about every time in terms of total internal drivetrain protection.
Won't help if the trans-axle/gearcase is tired, or has multi miles without much else done to it maint wise.

This OP's inquiry seems to only have 2K of mileage on it since "new"?
In my opinion also, it would be worth the inquiry to Rewaco to see what is installed or recommended for use in their vehicles for lubrication.
Best to use what is recommended or as close to what is recommended, for everyday use & peace of mind.

[DeathBySnuSnu]

Yep.
Was what I was thinking also.
With an upscale build like a Rewaco you would think they would start with a fully reconditioned trans complete with synthetic oil for longevity of box and a long time before an oil change.

Dont mix dino with syn.

Find out what they had in it. I bet it was not the old antique GL 4 and a half wore out box.