The manual transmission on a Jetta does not have a traditional dipstick. The fill plug is located on the left side near the front. If the oil reaches the bottom of the filler plug hole, the oil level is correct.
Top of the transmission...
2.3L of gear oil, Motul Gear 300 or Redline MT-90 or similar, 3 quarts
Its gear oil
If manual box then check all gear change linkages back to the box.
If your transmission is manual, you will have to change gear. If it is automatic, you won't.
Most manual transmissions use 80W90 gear oil. To be sure, check your owners manual. I have seen one use 30w motor oil.
You almost never check the A/T fluid with the transmission in gear. Check your owner's manual or look on the dipstick. If you have no owner's manual or it is not listed on the dip stick, call your local Ford dealer. Overfilling the transmission is a sure way to cause damage. You must check the fluid the correct way.
the synchronize in the transmission is bad, that why the jumping out of fifth gear
3,because the gear ratio in a manual transmission results is a gear ratio of about 3:1 for first gear.
Any Manual transmission can be towed with Manual Gear in Neutral; never engaged in a gear.
That manual transmission doesn't use gear oil. You can use Mercon ATF.
pull the check plug it will either be gear lube or auto trans fluid