Driving an 18 tonne tipper with a straight 8 gearbox, I was asked to drive an 8 wheeler tipper.
This was 12 years old. Got into the driving seat and the gears just put me right off.
The most complex gears I’ve driven was 4x4.
I understood the 8 x 8 arrangement, The fella told me it had twin overdrive.
can anyone tell me the sequence and if the overdrive is cancelled out when changing ratios?
I didnt drive it as it looked too complex and thinking safety first I backed out of driving it.
Sounds as if it could have been a 16 speed. This would be a 4 over 4 plus splitter. Were there 2 switches of some sort?
Pete 
a real gear box, 
Hello again…
sorry for the late reply… I dont get much time free to get online.
Yes It had the range changer switch and a rocker type switch on the side for the overdrive.
big heavy duty looking gearstick lol…
burnley-si: gulp 
lol
Yea so, whats the sequence for changing up through the range using the overdrive switch?
does the overdrive cancel if you change gear normally?
Ah you shoulda tried! It sounds like a similar set up to what I just learned with for C+E. Remember to take a pic next time!
(Although to be fair we didn’t bother with the splitter after the initial explanation/play we just used the 8 gears (4hi/4lo) Fully loaded it may have been more useful I guess)
coaster:
Driving an 18 tonne tipper with a straight 8 gearbox, I was asked to drive an 8 wheeler tipper.
This was 12 years old. Got into the driving seat and the gears just put me right off.
The most complex gears I’ve driven was 4x4.I understood the 8 x 8 arrangement, The fella told me it had twin overdrive.
can anyone tell me the sequence and if the overdrive is cancelled out when changing ratios?I didnt drive it as it looked too complex and thinking safety first I backed out of driving it.
Well firstly whoever told you it had a twin overdrive was talking ■■■■■■■■, it may well have been a double overdrive gearbox, but gear ratios of 0.85 and 0.73 will make no difference to how you stir the stick and all he did by giving you that information was confuse you 
It’s a simple thing really, the same as your four over four 8spd, but with a splitter on each gear, so 1lo/1hi, 2lo/hi etc etc. you put the stick in the 1st gear position then move the solitter switch to give you high and low, you could leave it in high and drive it as a normal 8spd, or leave it in low and go into high split in top gear only. or go up one and a half gears at a time.
It sounds a bit complicated, but it really isn’t, the best thing you could have (& should have) done was to get out there and drive it, play around with things until you get the hang of it. That’s how we learn 
thanks for all the info.
yea I thought he was talking ■■■■■■■■ at tthe time. If I get the chance of driving it again I will 