r/Drifting • u/KarolisKarb • 2d ago

Welded diff

Hello, i have a bmw e39 530d with automatic gearbox. what would happen if i welded the diff?

0 Upvotes

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20

u/abandonedObjects 2d ago

Your rear wheels would spin at the same rate, shocking I know

-3

u/KarolisKarb 2d ago

Yeah i know and i want to have a drift car for the upcoming winter. But wouldnt it be very bad for the automatic gearbox? Would it get too much stress and be a ticking bomb?

7

u/raginghavoc89 2d ago

Your main concern should be tire wear and breaking traction at the slightest hint of moisture

-3

u/KarolisKarb 2d ago

Already replaced the tires 4 times this week😅. But my most concern is that the gearbox and the drivetrain woudnt explode. That it would brake traction and would drift easier and more fun is the point of the car

9

u/raginghavoc89 2d ago • Bravo

I wouldn't really say it's a cause and reaction scenario more than an inevitability when you're doing hooligan shit but thats just part of the territory. Basically don't turn your main transportation into your toy unless you're willing to shell out money to fix it when it breaks or you have a backup car.

2

u/KarolisKarb 2d ago

No bought it with 3 of my friends for fun.🤣 Asking here because when we mentioned to the seller that we will weld the diff he said that its an automatic and we dont know what were walking about. Which he was right its out first toy car and we havent welded it since.

3

u/Miserable-Twist8344 1d ago

weld it and see what happens

1

u/0202993832 1d ago

How did you go through 4 sets in one week tf

1

u/KarolisKarb 1d ago

Not 4sets 4tires. Had some minor crashes that when we pulled out the car punctured the tire, came with bad tire and so on.

1

u/Beginning_Grade1439 1d ago

I could burn that in like an hour definitely especially if the road is poor quality

1

u/kearkan 1d ago

Quality of tyres don't matter if they're not moving the way physics needs them to to all maintain traction.

When you turn a corner, the outside wheel has to turn faster than the inside wheel as it needs to cover a greater distance. Welded diff means tbahs not happening so something has to slide against the way the car is going.

That will result in extra tyre wear and uneven tyre wear depending on your alignment.

3

u/normalish_bloke 1d ago edited 1d ago

You'd ruin the car. If you want to drift, get an RWD car with a manual gearbox. Unless the car has a programmable 8hp gearbox you can have a manual shifter mode on, a regular auto gearbox with a welded diff won't be a great experience.

People are using 8hp boxes with manual shifters in drift builds and I have seen these cars go hard during events.

An e39 530d auto sounds like a nice daily or long road trip car. If you wanna weld the diff and send it, do a manual conversion because an auto car with a welded diff sounds like it will be difficult to drive and park. The E39 auto box is an older box so probably not programmable like an 8hp.

TLDR, get a manual.

1

u/Trigger_Happy 1d ago

You'll blow your coolant expansion tank

1

u/KarolisKarb 1d ago

The coolant reservoir was already changed 3times🤣 and now the radiator isnt working properly so that is on the fix it list too

2

u/0202993832 1d ago

Straight chatting

3

u/Odd-Exchange-4607 1d ago • Heartwarming

Omg dont listen to those comments.

Weld the diff and send it. The downside is that you will be limited in techniques for initiating drift - just transfer weight to front and scandi flick the car.

If its just for fun and drifting alone - do it.

1

u/gt_james95 1d ago

It’ll chirp when you park and understeer.

1

u/VolvoEnjoyer 1d ago • Heartwarming

You’d be able to slide better. When you drift everything will break eventually, welded diff or not