I have a 1986 Honda Acty Truck 5spd. I was doing some servicing on it and wanted to change the gearbox oil. I managed to drain it from the drain bolt underneath. However problems arose when I wanted to re-fill the box. The fill plug was stuck fast, I tried a mechanic down the road and he couldn't shift it. However there is a Hex head bolt right next to it. He managed to remove that and fill the box up with oil although I was dubious it might be something important and shouldn't be removed? but i stupidly agreed to let him remove it. No springs or anything came out with it. On the Lings Honda diagram it shows it as a Interlock bolt. However the gearbox seems to make a slight whine in 5th since the change. I think it might be incorrect oil after reading and it needs some Honda MTF which I have ordered. Just wanted to know if anything could of dropped off inside the gearbox to cause any problems, the truck seems to shift fine. But without a service manual it worries me it might have caused some damage and I might need to strip it in the future. Thanks guys. Josh.
Try these links with Honda EPC parts catalogues + diagrams https://minitrucktalk.com/threads/parts-diagrams-parts-search-by-frame-number.17214/
