Just review for you

My Renault Grand Scenic IV

V-Belt Tensioner Story

First Workshop Experience
What happened:

They replaced your V-belt tensioner and tried to fit a new original V-belt (6PK1199).

They claimed the new belt was "Too long" (by 2mm), so they used your old belt (6PK1197) instead.

Result: The condition actually got worse after the change.

Doctor Gearbox Experience
What happened:

I went to Doctor Gearbox on 31/5/2025.

Ah Hui solved my V-belt tensioner noise issues.

Ah Hui successfully used the new original V-belt (6PK1199).

Result: The noise problem was resolved.

Why the Difference?
Same parts, different outcome:

Both workshops used the same parts, but the results were very different.

Experience and skill matter a lot—especially with French cars like Renault, which can be tricky to work on.

Proper installation and adjustment of the tensioner and belt are crucial for smooth operation and noise elimination.

Key Takeaways
Experience counts: A skilled technician like Ah Hui at Doctor Gearbox can diagnose and solve problems that others might miss.

Correct parts and fitment: Even a small difference in belt length can cause issues if not installed correctly or if the tensioner isn't adjusted properly.

Trust the experts: Sometimes, it's worth seeking a second opinion or going to a specialist, especially for complex or uncommon vehicles.

Yes, Doctor Gearbox Autos Specialist is highly recommended based on their extensive experience.

Thank you Ah Hui

I'm driving a semi fiat doblo I suspect there's some gear transmission issues so I went down to doctor gearbox when I reached 1 India guy attend to so I told him problem he took out a tab n plug in to my vehicle to diagnose then a Chinese mechanic ask me what my issue so I told him there's a clucking sound when my vehicle changes gear so he told me it could be my clutch pump issue so he suggested I change everything the whole set which cost 3-4k will solve my problem(what kind of advice is that it's like telling me car spoiled change car lor) WITHOUT EVEN TEST RUN THE VEHICLE or check on my vehicle and for the India guy disappear without even tell me the results this kind of advice any workshop also can give.Very disappointed I will go to my own mechanic and check and repair to see what the fault then I review again here to see is doctor gearbox right or not next week

Went down on Sunday to Dr Gearbox to check on my car gearbox jerking issue and funny noise coming out from the engine when accelerating hard. Lady boss Rose was kind enough to ask me to go down and have a check even though I am not their existing customer. They did a thorough inspection on the under chassis to ensure there are no leaks and afterwards the boss Ah Hui took the car for a spin to simulate what is the actual problem. After the car ride with Ah Hui, he open up the bonnet to do further analysis and low and behold, he discovered that there is a plug that was attached to the charge pipe actually came off. In the end, he attached it back for me and didn't even charge a single cent!!! Kudos to them,I will definitely trust them for any repairs and service in the future. To Ah Hui and Rose, you made my day. Thank you.

Am now driving a 15-year old Civic. Recently, my car will jerk when I shift from drive to reverse. Suspecting that it was a gear box issue, and after checking out the reviews online, I drove down to Dr Gearbox for a diagnosis. Managed to speak to the lady boss, Rose, and she suggested that I go for a transmission overhaul since I intend to keep my ride for another 5 years. The downtime was 3 days, as communicated, but my car was ready for collection by end of the second day.

Overall, I have a positive experience with the workshop - Rose is quick to respond to my queries, and not pushy throughout my whole engagement with her. Also, she provided me with updates on the overhaul progress - a big thumbs up!

Have been driving my car for a few days after the overhaul, and I must say Dr Gearbox has done a good job - my car is running great again, I am enjoying my ride even more than before.

I went there after reading on SG car mart feed back. After discussion I agreed to repair. Staffs are honest, hardworking and strong in technical knowledge as well. After serviced my car is very smooth and powerful. They are really Doctors of gearbox.
SAW ( RAV4)

Transmission oil tube burst and car can't move on a Sunday afternoon... Lady boss responded promptly and tow truck arrived quickly. The issue was dealt with professionally at the workshop and managed to drive off in a short while. - Sze Han Ng

When its time for servicing... I will ONLY send my car to Doctor Gearbox! My best mechanic & recommended! Trusted mechanic for my car needs! Thank you! Doctor Gearbox! - Martini Jamil

Very professional in car service. Lady boss Rose was very helpful and knowledgeable in sharing with me in car maintenance. Will go back to her again. Highly recommended 👍👍👍 - Alex Chan

FIRST TIME and never heard of this shop before. My car broke down( on sunday ) due to gear box issue and had to tow it to my usual workshop. SUDDENLY, i saw this workshop "DOCTOR GEARBOX" it looks professional by its name and made a call. A lady(rose) was very knowledgeable. By far, this is one of the best service car workshop I've been to. STRONGLY RECOMMENDED! Thank you to rose and team for your dedication!❤️ - Ewin Nabyll

F20 having some gearbox issues. Wanted seek second opinion. Called them and was welcomed to proceed down for a free diagnosis. Lady boss and William were friendly and knowledgeable with no hard sell. They also provide alternatives such as self source parts. Recommend to go down for a free diagnosis if experiencing gearbox issues. Although reasonably priced, it was too much a cost for an old car. So still considering to proceed or not. - zealous lim

Indeed doctors! Chance upon their name and decided to head over as we suspect issue in gearbox. They give professional advise and are very skillful to diagnose the problem. Was settled less than 8 hours. Also they provide free labour for engine oil replacement on every Sunday 😃 - Genconnect

I've been going to Doctor Gearbox for their great service and trusted advice. - Fazli Mansor

Boss Rose, so far, drive for 3 hours last night, never encounter lack of power or delay in acceleration. Kindly help to inform Ah Qiang after he had changed purge control valve and hose and intake manifold gasket. Shall monitor the car acceleration for the next one week. Hopefully, no issue arises. Many thanks to ur team help. 👍🏻 - Michael See

First time was here and lady boss and all the stuff was very friendly and nice 👍🏻 was doing a normal serving package with them using 5w40 Engine oil fully synthetic Ichiro made in japan 🇯🇵 my car very smooth ! They even help me checks on my car for any wear and tear 👍🏻 Lady boss even take drink and give me and my friends drink thank you so much know you all great place to come ! 👍🏻 - Ai Shen (Ah Bing )

Repaired gearbox recently. Very happy with the outcome. Staff are very professional. Just came for engine oil change. Bring your oil and filter and they change for you absolutely free. All welcomed, no need be existing customers. No gimmicks. - Louis Tan