80 auto and rock crawler gears problem.

[TheBigBoy]

Gday guys, I know alot of people here are running them and also fit them. But mine is playing up and I need some advice on what the problem is.

Poroblem 1. Its an auto 80 series and when driving at 100kph and then have the accelerator somewhere between accel and engine braking there is a grinding and vibrating noise coming from the transfer. (Ive redone the entire front diff and uni's on drive shaft)

Problem 2. When I purchased the truck it was sold to me with 45% rockhopper reduction gears. But when I put it in low range it just feels like a normal low range. But sometimes when I stop (eg. at the drive through the other night) high range in D. I take my foot off the brake and instead of wanting to pull away by itself it just sits there and when I try to accelerate it feels like its in rockcrawler gears (real slow).. Im worried that 1 day it might decide to do it when Im doing 100 and cause an accident.

Anyone else had these problems? Or know what it is before I go pulling it all apart.

Cheers BD

[Z()LTAN]

sounds like your low range isnt actually engaging correctly most the time.

Check your linkages.

It wont ever go into low range at speed, dont worry about that.

[dow50r]

guessing now that you have a 3+ lift and constant 4wd..the front uni angles not being equal are the cause of the vibration.
As far as rock gears go....r they just low range reduction or both high and low??
Andrew

[Auto-Craft]

45% reduction should mean around 40-45 kph top speed in low range in the auto, and about 68kph if they are standard gears.