4WD Bongo Front and Rear diff ratios

Technical questions and answers about the Mazda Bongo

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NZ Friendee
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4WD Bongo Front and Rear diff ratios

Post by NZ Friendee » Thu Oct 22, 2020 11:31 am

Hi i was wandering if anyone on here knows if the front and rear diffs on a 4WD bongo are the same ratio or has mazda geared them differently to compensate for the different sized tires they specify.
Bob
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Re: 4WD Bongo Front and Rear diff ratios

Post by Bob » Thu Oct 22, 2020 11:45 am

Hi. 8)

They'll be the same.

The different size tyres specified actualy have the same rolling circumference, which is vital so as not to fubar the transmission.

Many peeps fit the same size all round, but this must be the larger, rear, size for the load rating. :wink:
NZ Friendee
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Re: 4WD Bongo Front and Rear diff ratios

Post by NZ Friendee » Thu Oct 22, 2020 7:52 pm

Thanks.

Does anyone actually know for certain? I was just thinking someone here must have pulled one apart at some point.

I only ask because the previous owner of my bongo has fitted 205:70:15’s on the front and they are still in really good condition but the internet tells me that they are 1% bigger than the rears, while 195:70:15’s are 1% smaller.
I know that doesn’t sound like much but it equates to 1 less tire rotation every 100m with the pinion gear spinning many more times per rotation and it’s surprising how quickly 100m goes by at 100KPH.

If the ratios are the same front to rear I’m happy that I’m still about the same difference in tire size just in the other direction but if the ratios are different that’s another kettle of fish and I’ll be down to the tire shop lickity split.
Bob
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Re: 4WD Bongo Front and Rear diff ratios

Post by Bob » Thu Oct 22, 2020 9:07 pm

On this old thread one of our regulars states that the part numbers for the diff 'inards' are the same:

viewtopic.php?t=44397

Should be simple to confirm this. 8)
NZ Friendee
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Re: 4WD Bongo Front and Rear diff ratios

Post by NZ Friendee » Fri Oct 23, 2020 8:36 am

That looks fairly conclusive to me. I’ll keep my 205s till they wear out. Thank you 😊
Bob
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Re: 4WD Bongo Front and Rear diff ratios

Post by Bob » Fri Oct 23, 2020 9:08 am

I'd be happy, too. 8)
TimmyCarson
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Re: 4WD Bongo Front and Rear diff ratios

Post by TimmyCarson » Mon Jan 11, 2021 2:45 pm

"That looks fairly conclusive to me. I’ll keep my 205s till they wear out."
If you'll be looking for spares, you can also check 4WheelOnline. They have some of the most well-trusted tire brands to date. They are all also offered in various sizes, so you can pick the one that would work best for you.
Ian
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Re: 4WD Bongo Front and Rear diff ratios

Post by Ian » Mon Jan 11, 2021 2:56 pm

Cheers Timmy. I'll pass your details on to our one-and-only Mazda Bongo owner in the USA!
668. The Neighbour of The Beast.
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