4.8 auto engine braking question?

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hugejp
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4.8 auto engine braking question?

Post by hugejp » 28 May 2017 21:24

Howzit guys... question time.

I know that the auto 4.8 has close to zero engine braking (ok zero).

What I have noticed is that in tiptronic 1st gear there is some resistance on the decline & when in 4x4 LR this resistance is stronger, I recon this is not engine braking, but more gearbox clutch resistance, but I truly just dont know enough to be sure... (explinations pls)

So to the question - I feel more "engine braking" in LR, so...

Would this resistance be greater if I installed more aggressive LR gears from Marks4wd???

Opinions pls

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Re: 4.8 auto engine braking question?

Post by Peter Connan » 29 May 2017 05:45

It is probably torque converter slip, thus the closest you can get to engine braking in an auto.

Lower ratios in the transfer case will increase this, but I doubt the difference will justify the expenditure, thus if I was in a position to install such gears, I would not include this in the calculation of trying to figure out which ratio to get.
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Re: 4.8 auto engine braking question?

Post by Clem » 29 May 2017 09:22

The 4.8 auto will lock and hold a gear manually selected. High range I'm not 100% sure because I haven't fully tested it about but in low range I have tested it and it will hold the gear. On mine anyway. Not sure if it's different for different years.

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Re: 4.8 auto engine braking question?

Post by SJC » 29 May 2017 09:36

Ek sien die 4.8 auto het slegs 3.54:1 ratio diffs. Dit sal ook sekerlik 'n rol speel op die "perceived engine breaking"? Veral met groter bande op die voertuig.
Maar om diffs te re-gear sal seker net so duur wees....

http://www.marks4wd.com/diff-ratio-information

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Re: 4.8 auto engine braking question?

Post by Clem » 29 May 2017 09:48

Lower compression ratio of a petrol engine too. But first low does provide quite a lot of braking. Depending upon circumstances though one sometimes needs to use brakes too - but this is also the case on some of the older manually geared petrol Land Rovers too.

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