Ashcroft under-drive reliability for a tourer

[Steve223]

Hello,

Currently deciding whether to get crawler gears or Ashcroft under-drive. Really would prefer the under-drive for the tourer so I have more options my only concern is reliability as it ads another component and as I understand a failure with a under-drive would render the car undriveable. Looking for experience from people with under-drive and how suitable it is for a tourer where many K's will be driven.

Cheers

Steve

[Wicks89]

No PERSONAL experience, however when I was shopping around for my defender found a beautiful td5 110 with reduction gears that you speak of done up as a tourer.
The lovely old bloke that was selling it had everything installed (he had a huge list of mods and accessories) prior to doing several massive trips. Through the Simpson and the gulf etc etc.
obviously he was selling it but he said they went great and never had a drama with them. I believe him he sent me very comprehensive wad of information about it.
So I reckon reduction gears will definitely work. Hope this vague, unreferenced info helps

[Steve223]

Hi, so you have reduction gears or a under-drive? The reduction gears in transfer case will pose as much reliability issues as the regular transfer case as it it will only change the low rang gearing. Different with a under drive where you bring another element in to the equation

[Robmacca]

Hi, so you have reduction gears or a under-drive? The reduction gears in transfer case will pose as much reliability issues as the regular transfer case as it it will only change the low rang gearing. Different with a under drive where you bring another element in to the equation

Can I ask a stupid question here.... what is this "another element" that u mention.....?

[Steve223]

Can I ask a stupid question here.... what is this "another element" that u mention.....?


the under-drive is the other element

[Psimpson7]

I have zero concerns with reliability with my underdrive.

[Steve223]

I have zero concerns with reliability with my underdrive.


You have the Ashcroft under-drive? How long do you have it for, used on a tourer or only play car? Cheers

[Psimpson7]

I do indeed. I think I got it in 2011 but I need to check that

it is fitted on my td5 which is my tourer and play toy so it cops a total pounding.

Things to be aware of. Its another large heat source. Its heavy and it is driven through all the time.

We have 3 cars fitted with them who all use them in the group of mates i drive with and I have driven a few mates cars in the uk who had them well before I did. No one has had any issues I am aware of.

I have probably done 25k on mine now inc a long trip to tassie.

there are another couple of members at least on here who also have them aswell.

[Steve223]

Thanks a lot, good to hear as I very much prefer the flexibility of the under-driver over crawler gears

[bushrover]

Had one in my Defender for 3+ years. Haven't even given it a second thought until now............maybe I should pull it out to check for wear. I do change oil more often and have never had any excess wear material. It certainly quietened down after a few thousand K's, probably has 50000 on it now. I tow a 1200kg camper (been pulled up a few times for excess speed while towing) and use the underdrive a lot in tight and rocky stuff.

I do have to pull the transfer case to fix oil leaks, so will check for wear and post up a few photos when I do.

Rick

[bushrover]

Well, certainly took my time to fix the oil leaks.......................... and post a few photo's -

All the bits -
https://www.aulro.com/afvb/images/imported/2015/05/689.jpg


Shiny bit of sun gear runs on a thrust bearing. Doesn't look as if there has been any movement on this surface......however....
https://www.aulro.com/afvb/images/imported/2015/05/690.jpg


on the opposite side of the thrust bearing I have wear on the planetary carrier...................
https://www.aulro.com/afvb/images/imported/2015/05/691.jpg

and the thrust bearing -
https://www.aulro.com/afvb/images/imported/2015/05/692.jpg

Planetary pins are loose in the carrier and two have moved and were rubbing on the aluminium selector fork (Pins are punched each end to lock them in place. You can see the square punch marks in the photo's. I have spot welded the pins on one side) -
https://www.aulro.com/afvb/images/imported/2015/05/693.jpg

You can see the two loose pins about 1-5-2mm further out. The right side is the selector side -
https://www.aulro.com/afvb/images/imported/2015/05/694.jpg

You can see where they have been rubbing in high ratio....about 2:30 and 8:30 positions and where they have been rubbing on the full surface of the selector fork in low.
https://www.aulro.com/afvb/images/imported/2015/05/695.jpg

I didn't get a photograph, but there is a bit of wear on the centre shaft where it runs in the input gear bush.

I have to say there has never been any metal on any magnets in the past, however this time there was a fine smear of ferrous metal on the magnets and aluminium paste in the input shaft area where the oil drains back to the transfer case, plus a bit of thrust bearing material as well.
This must have done 60000km by now, some of it in low low dragging the camper in to areas it shouldn't be. With lockers front and rear, atb in the middle and super low low range, the old girl is pretty unstoppable.


Rick

[Pateyw]

Had mine in now for a long time and around 30000k
Done a few trips cape ,kimberly, Simpson and all the tracks in those locations .
Never any issues .
Pulled it down recently while I had transfer case out fitting 1:003 gears .
It was as good as new and very well made I was impressed with how good a condition it was in .
The only thing I would say it adds heat .

[Steve223]

I pulled my one out and sold it, realised I don't need it in the tourer, it needs more attention to ensure all bolts are tight as they loosen itself and I did not like having the weight hanging of that short bolts which are a bitch to access. not to mention the initial problems when Ashcroft deliver it with grub screws which where 2mm to long and allowed a leak to distribute transfer case oil everywhere... for my tourer KISS