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Pauly boy
4th January 2014, 06:40 AM
Hi all
first timer so be gentle just wondering witch would be the best ratio for 35s in a 99 td5 defender ? I ran 4.5s in my old 73 series cruiser without to much difference to low range

Blknight.aus
4th January 2014, 07:15 AM
Depends on what you're after and your driving style

4.11's will get you back to close and 4.7's will get you a tad under.

the td5 will motor along on the 4.11's quite nicely but will be a tad under on acceleration, which if you dont tow heavy or drive like a ricer will be almost unoticable.

the 4.7's will cut your top speed a bit but will give you a bit more pull. It will also drop your crawl speed a touch which also gives you a bit more reaction time when reversing or low ranging.

Pauly boy
4th January 2014, 07:41 AM
good to know cheers now best of both worlds 4.7s with disco high range with defender low range ?

Blknight.aus
4th January 2014, 08:13 AM
low range remains the same across both.

ITs been a while Id have to sit down and nut out the differences between the 1.2+1.4 with the two different diff ratios.

Slunnie
4th January 2014, 08:17 AM
But 4.7:1 gears have smaller and weaker mesh area due to the pinion size and is not up to use with 35s.

Pauly boy
4th January 2014, 08:46 AM
Is there after market gear set strong enough to take on 35s (and the odd dose of red mist) thanks for the input :confused:

Blknight.aus
4th January 2014, 08:50 AM
But 4.7:1 gears have smaller and weaker mesh area due to the pinion size and is not up to use with 35s.

just peg them and they do fine.

Slunnie
4th January 2014, 05:05 PM
just peg them and they do fine.
Not likely. The rover pinion is just too small.

Bush65
4th January 2014, 05:37 PM
Ashcroft heavy duty ring and pinion with reverse cut (http://www.ashcroft-transmissions.co.uk/index.php?act=viewCat&catId=12) are the strongest that suit your rover front diff, but you would need to research to find what of those ratios, can be matched with available ratios for your rear Salisbury diff.

You may need to look in the USA for suitable ratio Dana 60 ring and pinions (the Salisbury is based upon the Dana 60. There are some things to watch so come and check back here if you decide to go that way. For example thickness of ring gears (both Salisbury and D60) change at some ratio point, which I can't recall of the top of my head.

Arcadeus
13th August 2014, 09:27 AM
Great Basin rovers in the USA make a very strong 4.43 that I use with my 35s... Good middle ground between the 4.11 and 4.7... And shipping is relatively inexpensive...

MLD
20th August 2014, 09:35 AM
I second chatting to Bill Davis from GBR Utah on the ratio options. The man has endless energy to impart helpful and knowledgable information.

As for mis-matched ratios, without commenting on the appropriate nature of that approach, I know that Wayne runs (or did run) 4.11 rear and 4.12 front. Mike runs 4.11 rear and 4.14 front. Mike discussed his set up with Bill Davis at length before committing. I went with 4.11 front and rear bought from GBR.

Don't quote me on this but I understand that the 4.7 ratios require shims or other minor mods in the Salisbury. Not that would be a major hurdle, it is just not a straight bolt in.

Have a look at Ashcroft's ratio calculator on their website to see the effect of the different combinations of ratios.

My 4.11's reduced my overall ratio by 8.6% (puma gearbox) and I like the lower gearing both on and off road. It is a compromise (read PITA) in traffic but I don't commute with it.

MLD