89 manual loud as hell!

[CrustyJunker]

Almost sounds like universal joints to me. I know there's a lot going on in this thread, and it could be a number of things...My best advice is just check the simple stuff first!

 

[MLX10]

Almost sounds like universal joints to me. I know there's a lot going on in this thread, and it could be a number of things...My best advice is just check the simple stuff first!

I agree. I will most definitely cover all simple and less expensive bases first. Fluid, U bolts, etc.... I'll post an update with some pictures and possibly a video after I get a chance to get some things done.

 

[Biggershaft96]

Damn. Expensive as in over $1000 all said and done? Before I take that leap of faith I'm going to make sure I diagnose it correctly and do all the minors things first.

not sure, ive never paid anyone to pull my trans but if i had to guess itd probably be around 1000 at a shop. Make sure you check everything over good and get some fresh fluid in it first. Try to wiggle your engine and trans with a pry bar to check the mounts, as well as lookong them over to make sure the rubber is still in them.

 

[sketchy90z71]

Yea unfortunately these trannies have an integrated bell housing so you have to drop it to do just about anything. I second the pilot bearing or throwout bearing. Mine had less than a quart of fluid in it and I never had a sound like that. They also are a bit notorious for gear rattle and bad input bearings and that is just an awful sound but not what you're describing. I just hope you have a 2wd because the transfer case on 4x4s makes dropping that trans more of a ***** than it needs to be.

 

[bowtie-72]

I think I would have to agree, change the fluid first then if that didn`t cure it, drop the tranny and take a good look at the entire clutch assembly.

 

[JCribb]

I'm not a fan of the HM290/ NV3500 trans. I've had three of them in my truck, and every one of them had an issue even a "performance built" one that was supposed to be an upgrade was junky. I've had input bearing issues from two of them, a broken 1-2 shift selector, bad bearings on the 3-4 shift rail, and general sloppy grinding mess.

My engine is not stock, so that did play into some of my issues. I have since upgraded to a NV4500, and all my troubles are gone.

I have had two shops tell me to run full synthetic 5w30 engine oil. I'm still a believer in using synchromesh oils. With all my listed problems above, my oil level was spot on, so I believe it's just the design of that particular transmission.

My assessment is the HM290/NV3500 is great for the 4.3 V6, and if you have a V8 and you tow a trailer, just step up to the NV4500 and avoid the hassle.

Keep in mind this is just my experience with the transmission, others may not agree with me, and I'm okay with that.

 

[MLX10]

Well I finally got around to changing the fluid today. I haven't been driving it since it's my second vehicle. The fluid seemed fine...but I changed it anyway with pennzoil synchromesh. I guess I'll replace the u joints next.

What I forgot to mention which is probably very important is that the engine is not stock. It has upgraded cam, headers, straight pipes, and a CAI and a mysterious chip (that I don't know what kind it is. The previous owner did all of this to the truck. It is also clear that it has been neglected for quite some time.

 

[MLX10]

Check the fluid level in the transmission. My truck is an 89 with the same transmission. It will have a 5LM60 if it is the original trans. They take two quarts of synchromesh fluid. Get the stuff found here http://www.ebay.com/itm/161475758781?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

You can also find the fluid at your local NAPA or auto parts store.

I will tell you, this transmission is a little notchy, it shouldn't make those kinds of noises though. If it makes noise when you push in the clutch, the throwout bearing is likely bad. My trans is a little notchy and has 150k miles on it if that is any consolation.

Anyway, the fill hole is the plug on the passenger side of the transmission on the picture below. The drain is on the bottom of the transmission. Both take a 17mm hex head to remove it. My advice is get a bolt with a 17mm head on it, put a nut on the threads and weld the nut to the threads. Then you can use the head of the 17mm bolt as the hex head, much cheaper than buying one.

Drain the transmission by removing the bottom plug until it drains completely. Replace the plug and then pull the side fill hex head and fill it until it starts leaking out. Take it for a drive afterwards and see if it is any better.

You must be registered for see images attach

So I changed the fluid with synchromesh a well or so ago. It does seem a lot better. It's by no means smooth but I'm wondering if you'd classify it as a little notchy lol.

 

[MLX10]

I'm not a fan of the HM290/ NV3500 trans. I've had three of them in my truck, and every one of them had an issue even a "performance built" one that was supposed to be an upgrade was junky. I've had input bearing issues from two of them, a broken 1-2 shift selector, bad bearings on the 3-4 shift rail, and general sloppy grinding mess.

My engine is not stock, so that did play into some of my issues. I have since upgraded to a NV4500, and all my troubles are gone.

I have had two shops tell me to run full synthetic 5w30 engine oil. I'm still a believer in using synchromesh oils. With all my listed problems above, my oil level was spot on, so I believe it's just the design of that particular transmission.

My assessment is the HM290/NV3500 is great for the 4.3 V6, and if you have a V8 and you tow a trailer, just step up to the NV4500 and avoid the hassle.

Keep in mind this is just my experience with the transmission, others may not agree with me, and I'm okay with that.

If I were to upgrade to a NV4500 what would I have to change?

 

[JCribb]

If I were to upgrade to a NV4500 what would I have to change?

Find you a 92-94 1 ton with a 350, everything lines up and bolts up. The NV4500 has a bell housing that is separate from the transmission, that is the hardest part to find because greedy people try to make extra money off just the bellhousing. Most listings sell just the transmission without the bellhousing. If you have a self pull salvage near you, that's where I would look, or if you got a buddy that has a rusted out beat to hell one ton, that's where I would really start drooling because you could get everything you need right there.

I honestly looked and searched for 3 months before I got lucky with my find.

You can buy a reman NV4500 for roughly $1500 without a core ($500 core charge at most places). I bought mine used for $350 from a scrapper, and dropped it off at my transmission guy and had it gone through and installed for another $1,000.

The 88-95 slave cylinders are external, the 96-up are internal slave cylinders. 95 has a different gearing from what I have read, as opposed to the 92-94 6.34:1 first gear. I wanna say it's like a 5.xx:1 something, but I can't recall for sure.