Auto Troopy Gearing
Submitted: Monday, May 06, 2013 at 09:26
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rb30e
Hi all,
I have recently purchased a 75 series troopy fitted with an 80 series auto transmission, which is a direct bolt on.
I can't drive manual any more because I'm paraplegic.
We took it for a run up the freeway to
newcastle on the weekend and found that it seemed to be sitting on quite high Rpm.
2600rpm at 110kph
and
2400rpm at 100kph
It was definitely in top gear also.
Just want to get an idea of what the normal Rpm whould be at these speeds with the factory 5 speed manual.
Cheers
Reply By: Geoff (Newcastle, NSW) - Monday, May 06, 2013 at 09:40
Monday, May 06, 2013 at 09:40
In a 78 Series you are doing 1,000 rpm per 40 km/hr in 5th gear.
Therefore at 100 km/hr my 78 would be doing about 2,500 rpm.
Yours sounds about right.
Hope that helps.
AnswerID:
510423
Reply By: get outmore - Monday, May 06, 2013 at 11:59
Monday, May 06, 2013 at 11:59
As said.
Thats right 40kph per 1000
AnswerID:
510437
Reply By: TerraFirma - Tuesday, May 07, 2013 at 14:37
Tuesday, May 07, 2013 at 14:37
Hi RB, Sounds like it's the correct RPM but you bring up and interesting subject. I'd love the new 70 series but it's only available in manual also. Not withstanding your scenario I'd love an auto for towing but I understand the 70 series to be discontinued in the future.? The new 200 Series Turbo Diesel does 1600-1700 rpm at 113KMh which is around 1000 rpm lower which shows you how things have changed with more gearing. You may be able to change the diff ratios to lower the rpm but I'm not sure how that would work with the 75 Series engine.?
AnswerID:
510514
Follow Up By: Member - Boo Boo (NSW) - Tuesday, May 07, 2013 at 18:58
Tuesday, May 07, 2013 at 18:58
Your revs are spot on.
I had a 1995 75 series troopy and it sat on 2400rpm doing 100kmh.
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Reply By: Bob Y. - Qld - Thursday, May 09, 2013 at 11:37
Thursday, May 09, 2013 at 11:37
rb30e,
A cheaper alternative might be to change the ratios in your transfer case. I looked at this a few years back, but still haven't done anything.
Terrain Tamer make a number of ratios to suit 80 series and others, and they offer one that keeps the same low-range ratios but high range is reduced by 9%. This gives, from memory, about 2100rpm @ 100kph. The new gear set is a direct changeover, I believe, with no machining required.
Mark's Adapters make some similar products, but am unsure of their ratio choices. Also their system is more sophisticated, and requires some machining to accommodate the new bearing structure.
Might be a cheaper alternative to sourcing a 5 speed auto box?
Bob.
AnswerID:
510631