I have the same problem. It started from 1st gear then move to 2nd gear shift and now up to 4th. You can save your money and time in the early stage but, if it gets worse then there is no solution other than to replace complete gearbox.
I had only 8 months of driving experience and I learnt lots of things from driving to car mechanical, electrical to denting and painting etc. Well, when I purchased Suzuki Mehran VX 2008 it's gear box was in good condition but sometimes shifting from 2nd to to 1st gear was hard. So in the early stage this small gear box bug wasn't caught by me and after some month I realized noisy sound when after shifting 2nd to 3rd gear during releasing releasing foot race lever. I ignore this shit noise and after 3 months I was in long route from Lahore Islamabad. When I came back Lahore from Isl.. I heared a very weird sound while my releasing foot from gear lever but this time the gear was 4th than the 3rd one (3 months back ). Sometimes little ignorance makes big mess with car. So be quick and try to fix the and maintain the car ASAP.
I have some tips to for the long life of gear box:
#1: Check your fluids.
It may sound simple but keeping an eye on your transmission fluid is one of the most effective ways to take care of your auto’s transmission that there is. This will also allow service techs and mechanics the opportunity to identify any potential issues, based on the level or absence of fluid. Often times leaks can cause problems so identifying a leak before it becomes and expensive repair is very important for your transmissions health.
#2: Give your transmission a boost.
There are some great products on the automotive market that can significantly increase the life of your transmission, and improve the performance of your vehicle.
#3: Give your brakes a break.
Riding the brakes of your car or truck can cause issues over time with your transmission. Pay attention to how often you apply your brake, and resolve to down-shift whenever possible. This isn’t always an option for folks with automatic transmissions.
#4: Keep it in gear.
Be aware of what gear you are driving in. Repeatedly driving 45mph in first-gear will cause trouble for your transmission over time. Likewise, when driving an automatic, be sure that you are in the recommended “drive” mode before heading out. Most drivers who own a car with manual transmission know what their doing. But they often lend out their car to others who don’t exactly know how to drive a stick. A lot of damage can be done to the gears if driven improperly. Make sure before you let someone else drive, they know what their doing.
#5: Shift only after you stop.
When switching from first to reverse or vice versa make sure you come to a complete stop before shifting in and out of gear. Shifting between these gears while moving could weaken or strip the gears of the transmission if done consistently.
#6: Take time to tune-up.
Don’t miss your regular tune-up appointments. A faulty engine can wreak havoc on the transmission, and can make it work harder than it should have to when shifting. Everything is connected in a car. Check your alignment, get your tune ups, and take care of the overall health of the rest of your vehicle and your transmission will benefit.
#7: Let it get warm.
Take time to warm your vehicle up before dropping it in gear and driving. This applies to both cold-weather and warm-weather driving. Give the vehicle five minutes to idle before taking off. This is especially true during the cold snaps. Let your vehicle warm up before changing gears and be safe when you’re out driving in bad weather this winter.
#8: Use caution when helping out others.
Think twice before offering to tow or haul vehicles or other heavy loads with your vehicle. The added weight can cause wear and potential issues for your transmission, unless you have a heavy-duty vehicle that is designed for such utility. Instead, be helpful by offering to call a tow-truck!
#9: Address repairs and concerns quickly.
Don’t delay in having your vehicle looked at when you notice signs of a transmission issue. This might include a strange smell, grinding when shifting gears, or an unusual sound. Failure to promptly address these concerns could result in a far more serious and costly problem.
#10: Keep things cool.
If you put your vehicle through its paces, the rough terrain, added weight, and heavy utility can generate heat, which wreaks havoc with a transmission. Cool down your transmission by installing an auxiliary cooling system or fan. Talk with automotive experts regarding the most practical options for your specific vehicle.
With a little care and cognizance, your transmission should serve you well. The benefits of putting a little effort into maintaining your transmission will pay off in reduced repair costs, increased reliability, and elimination of headaches later on!