Outer Limits 4x4 Board

On my way up to Inskip today, I lost boost on my 82 Tubro Diesel Triton.
When i would use the accelerator, it would spool up for a bit then bog down....(so to speak)

Any ideas on what this is....

Obviously I didn't get up there....Need to get it fixed asap

Does anyone know of a good TD mechanic down logan way?

What was it actually doing?
did it just hold revs? run rough?
does it idle normal ? does it revs out normal when in nuetral?
at what revs does it start to "Bog Down"
1st points to check Air filter = blockage/restriction
fuel filter- Have you touched it recently? Slight blockage
any unusual noises etc?

hope this helps
cheers