Hi everyone, new to the site and Isuzu. I just got a 91 2.6 5spd 4x4 181,000 miles that had been sitting for three years. It needed a fuel pump, I did that and seafoamed the oil and fuel system, changed out some exhaust gaskets, and put in a new radiator. It runs good, but I do have a couple of issues. The throwout bearing is definitely having problems, its pretty loud in neutral, also the clutch engages really low but the clutch master isnt leaking and shifts pretty smooth, sometimes 1st gear is tough, I put fresh lucas fluid in it. In fifth gear its really toothy, when you shift into it it helps to slightly rev it up for engage smoothly and on decel in fifth it has some backlash and rattles, you can feel it in the stick. It feels like the gears are knocking against each other. I wish it was just a really bad throwout bearing or clutch but I seriously doubt that. Sorry for the long rant but I really like the truck and would like to get it right, any help or insight on past experiences would be greatly appreciated.

Loud in neutral could indicate a siezed pilot bearing. It will beat up the end of the transmission shaft so replacement should be sooner rather than later. Any vehicle that sits that long can have problems from gummed up fluids; especially brake fluid which has an affinity for accumulating moisture. You might want to pop off the clutch slave cylinder and check the the o-ring seals and cylinder walls for corrosion/wear. Fresh Lucas? In what? Transmissions are pretty picky about lubricants. My 2x4 takes plain 30w non-detergent motor oil. Did you put the right stuff in?

I put lucas in the tranny, 80-90 weight like the haynes manual said, its what I have to go from right now, never owned an isuzu before, I can tell you all about RX7s, got 2 of those. It said to put dexron III in the transfer case. I I do plan on getting the tranny rebuilt, anyone else have any fifth gear problems before?

NO! NO! NO! NO! NO! NO! NO! NO!!!!!!! Drain the transmission and transfer case NOW!!!!!! Don't drive it any at all until you've done so.

Both the transmission and transfer case take 5w30 ENGINE OIL. It's even stamped on the fill plugs. Drain it well, top it off with engine oil, and drain it in a couple hundred miles. Do that a couple of times to flush the gear oil out and hope you didn't ruin the transmission. <img src="/forums/images/graemlins/barf.gif" alt="" />

Richard <img src="/forums/images/graemlins/patriot.gif" alt="" />

Get that out of there immediately... then flush/fill/drive/flush/fill/drive with engine oil a few times. The 5-speed takes engine oil, 5W30 or 10W30. Gear oil will trash it.

WOW That is disturbing, I only drove it home from work after doing so, I was just going off the haynes, thanks alot for the heads up. It had gear oil in it before, probably the reason I have a problem, again thanks, dont think its had time to do too much damage, it acted the same. I will double flush it [color:"red"] [/color] ASAP . I didnt see anything on the plugs, guess I get to start out as a big moron on this forum, looks like the rebuild could be inevitable. <img src="/forums/images/graemlins/confused.gif" alt="" />

I was just going off the haynes,

Go back and take another look. 5w-30, page 30. It does list 80-90W for the diffs right under it, but...that is pretty much death for the MUA5.

Michael

IF YOU ONLY DROVE IT A SHORT DISTANCE THE LIKELY HOOD OF DOING ANY DAMAGE IS PRETTY REMOTE BUT YOU SHOULD GET IT OUT OF THERE AS SOON AS POSSABLE ,, GET THE TRUCK UP ON JACK STANDS AND DRAIN THE TRANS AND THE TRANSFERCASE AS COMPLETELY AS YOU CAN , LET IT DRIP FOR AN HOUR OR SO, THEN REFILL THE TRANS AND THE T/C WITH KEROSENE AND START THE ENG AND LET IT IDOL IN NEUTRAL FOR ABOUT 30 MINUTES OR SO , AND IT WILL DILUTE THE REMAINING HEAVY OIL , DO NOT USE GASOLINE OR ANYTHING VOLITILE , NOW DRAIN THEM BOTH AGAIN AND REFILL , WITH 5W30 OR 10 W 30 AND YOU SHOULD BE OK, IF THE KEROSENE COMES OUT HEAVY COLORED YOU MIGHT WANT TO RINSE IT OUT AGAIN AND THEN LET IT DRIP DRY FOR A WHILE .THE KEROSENE WILL LUBRICATE THE BEARINGS ENOUGH THAT THEY WILL NOT BE DAMAGED AND ALL SO WILL NOT DAMAGE THE SEALS , JERRY

Well over the weekend I flushed the trans twice, plan on doing it a third time, just want to put a few more miles on this oil first. It dosent sound or act any differently but I'm sure some damage could have been done. I am currently looking for a good deal on a rebuild, I put a couple hundered miles on it already since the flushes, still kicking for now. Thanks for the heads up

Well since my last post my 5th gear did finally give out, I replaced the tranny with one from Midwest Auto Recycling. According to them it had 66,000 miles on it (supposedly CARFAX certified, but who knows). The only thing is that it has a bearing noise on decel and forth is just kinda noisy, not real loud but its there. I called them and they said to give a week or two and the bearings should quiet down with time, and its common since it was sitting for awhile. Its not the ujoints because when I push the clutch in it goes away, and it just isnt a ujoint kind of noise. Is it common for the MUA5 to have a little bearing noise, and is there an additive that anyone has used that might help with this?
I did put in a new clutch, press plate, throwout bearing, and pilot bearing, also rear main since I was there. Oh yeah-5W30 castrol- Any help is appreciated, thanks in advance,

Luke