"The loud roaring on start up is the lion waking up from its sleep"...

That is the funniest thing i have heard in a long time....outstanding bundu!

 

Bundu . . . you are correct, it's coming from the SIA.

Another one for you . . . are you familiar with the vehicle vibrating at around 75 mph. The previous owner had it checked out by Land Rover and said it was fine, but it doesn't seem normal to me.

Thanks for all your help!

 

Vibrations are an indication that something is wrong - its never normal.
First question: have you rebuilt your front drive shaft? Vibrations from 50mph onwards normally come from a drive shaft going bad.
If only at higher speeds then check your wheel balance, if the steering wheel shakes then its your front wheels, otherwise rear wheels.
Do you have non-D2 rims on your truck?

 

I have the original D2 rims on it. When I bought it, I had new tires put on along with a 4 wheel alignment. The steering wheel does not shake and I don't believe the front drive shaft has ever been rebuilt.

 

Well start by checking the u-joints and center ball joint on the drive shaft, they fail and explode your tranny. Signs of failure are vibration, chirping and a load boom. It's good preventative maintenance to haul it out and replace the u-joints and ball joint, look in the "Write ups" and "How To" section for details on rebuilding your drive shaft.

 

Look at this thread if you seek motivation:
https://landroverforums.com/forum/sh...ighlight=siked

 

When my a/c is on, there's a loud whining noise also during accel (I think my disco sounds more like a dump-truck lol). It's definately the viscous fan on mine. I'm pretty sure that the fan is engaged at full-power when the a/c is on.

As for your vibration at 75 mph, mine also does the SAME thing lol. The dealer told me that "It's normal". I haven't really investigated far into it, I'm rollin' on the original front drive-shaft, so i'm assuming that's what it is, since I have newer tires that have been freshly aligned.

 

The a/c compressor places extra load on the serp belt only when a/c is on and the a/c clutch has kicked in, otherwise the a/c pulley rotates free. Your serp belt slips if your serp belt tension is too loose and the a/c compressor is engaged, that is when you hear the squeal, especially when you punch the gas. The same happens if you get water splashed on the pulleys from a puddle or rain.

 

STOP driving the vehicle until you can positively confirm that the driveshaft has been rebuilt and that it is not about to go. As mentioned above when they fail on the DII they take out the tranny and that is big bucks.

 

Turns out the vibration was coming from a bad tire even though they are brand new. Two different garages used a run-on lift and agreed that was the problem. Everything else checked out on the truck.