Faint knocking - Rocklobster issue?!

Hi all,

After a day of driving in the snow and Ice I have noticed an annoying noise. I will try and describe it as good as I can do.. so it only happens in 4wd (2wd and 4wd low are fine), I would say it’s most noticeable when going about 30mph, happens when you take your foot off the accelerator after accelerating and then also when you first put your foot back on the accelerator after not accelerating at all. It lasts about 1 second. Hard to describe the actual noise but it sounds like a faint knocking almost. I have only really noticed it after fitting my Rocklobster 5:1 box but then again I have hardly driven in the snow and in 4wd at speed.

Thanks for your help.

Redmond

worth checking the UJ ? Think I need to replace one of mine.

Forgot to mention the front and rear props are brand new and it’s only the intermediate prop that is old - but even if the UJ was gone in that I don’t think it would only make the noise in 4wd?

No packed ice on the car and I made sure I put it back into 2wd if I got onto any grippy surfaces

Does the noise sound almost like a steam engine 'chuffing' like a knock but not quite that clunky? if that makes any sense? our 6.1 box started making a similar noise, some of the bearings were ruined, and that's the closest way i can describe the noise, we thought it was the intermediate prop at first. Transfer box was built with new TG gears, had an oil change and had only done 3-4k miles so wasn't expecting anything in it to have gone wrong- but there we go!

Thanks guys!

Transfer box mounts and bolts all look fine to me and are brand new.

I doubt it would be the bearings in the Rocklobster transfer box as they have literally just been changed / tested and I have covered less than 50 miles on them! I could send you a video of the noise if you like - just to see if it sounds exactly like the noise you describe - PM me if you like.

Interesting how you mention the intermediate prop as the UJ on mine does have some play - I am swaying towards this being the issue. I have also been told it is common for the intermediate prop weight to foul on the gearbox linkage frame, but no sign of this.

I think the best thing I can do is to get a new intermediate prop?? - does anyone know where I can get a new one from? One that is the right length would be a good idea as I am currently running a 25mm spacer.

Is the rocklobster from Richard Redacted ? He might be a good person to ask about the prop

I'd start then with the intermediate prop if the bearings ect are all new in the T-Box, The noise mine made was very specific and if it was doing it you'd see what i mean about it sounding like a 'chuffing' noise. Good luck getting it sorted!