Good Car with bad service support

After studying, reading reviews and comparing cars I finally chose to buy a Cheverlet Magnum LT, white colour.
Being a top end model, it has most of the basic features.
The car is good,  But Unfortunately I landed up in a manufacturing defect of tyre and the trouble began.
The problem is that car vowels at low speed of 30-40kmph (this started at 2000km)
I first checked the alignment and balancing but it didn’t worked so I registered complaint to the dealer.
Later came to know that this is a problem of Goodyear tyre.
So the respective engineer checked the tyres 2 times, when I was asked to bring the vehicle to the service station.
All in vein.
The service station is 100km from my place and I am asked to bring the vehicle again and again for checking.
Once I sent the vehicle and the engineer didn’t turn up.
No one is bothered to take care and you feel angry after paying 11.75lacs.
Or otherwise the car is good.
Good Points:
Good exterior. Leather upholstery. Excellent power and pick-up.
Bad Points:
Noisy engine at low speeds. service support!! lack of 6th gear.
This is a big drawback. Company should have provided 6th Gear. At 140 car is at 3000rpm and I don’t feel like stretching it further. (My Scoda Laura instead catches up 160 to 180 easily because of the 6^th Gear.)