By Tate on Tuesday, June 12, 2001 - 12:51 pm: Edit

Hello,
Right now my disco is in pieces. I'm in the process of having the rear u-joints replaced. I had seen that the fronts take generic part #369, however, this is different from the rear. Does anyone know the correct part number for the rear u-joints? D-90 faq lists #344 and #280. These are evidently not correct for the non-rotoflex D1 (98) rear shaft.

Thanks for a quick response

By RVR OVR (Tom) on Tuesday, June 12, 2001 - 12:57 pm: Edit

If all else fails, you can get them shipped next day or something from xks. They have generic ones for 18.66 each...I have them and they work fine.

http://www.xks.com/rcatdriv/rrcat52.html

Tom

By Tate on Tuesday, June 12, 2001 - 06:58 pm: Edit

Luckily ended up sourcing some locally, but thanks for the tip on xks--I hadn't heard of them before.

By RVR OVR (Tom) on Tuesday, June 12, 2001 - 07:51 pm: Edit

Tate,

Where did you get them and what were the part #'s?

Tom

By Tate on Wednesday, June 13, 2001 - 10:58 am: Edit

$300 just to replace the two rear u-joints, the highway vibes are still there, and the "Rover" tech didn't know that the Disco was full-time 4wd--I'm not going back there. I just called the parts lady, who said they ended up using Precision #344, not sure where they sourced them. Ah, the shop lied. They had told me earlier that this size wasn't correct. Precision seems to be a very common brand. I know that the All-Pro parts place I deal with carries them, though, and they're mentioned on the D-90 faq.

By RVR OVR (Tom) on Wednesday, June 13, 2001 - 01:45 pm: Edit

geeze! that is a lot of bank for a couple of u-joints.

what is the layout of your truck, maybe the folks here can help decipher your vibes....

By Tate on Wednesday, June 13, 2001 - 02:42 pm: Edit

The truck is a pure-stock 98. No lift. Light offroading. 60k miles. I've been through all possibilities of tires (rotated, balanced, aligned), and greased u-joints (back two are new). It's a speed and load dependent vibe, most noticeable between 45-65 mph, accelerating up a hill. It's not tires as it's not purely speed dependent. It's classic u-joint symptoms, but no one can find anything immediately wrong. I'm taking it to a driveshaft shop next week for front u-joints and to have both of them balanced. After that, who knows. I took a look at it and didn't see anything horribly wrong. I've had three places look at it. Experienced Rover shop (supposedly) said "It's not u-joints; it's tires." Tire shop said "it's not tires." This last place said, "it's u-joints." Admittedly, the new rear joints did help with low-speed vibes. At this point, I think it's just time to continue replacing the cheapest components first (u-joints), have the shafts balanced, and if that still doesn't fix it, go from there. (driveshaft splines, transfer case output bearings). But I won't go back to the last place. Am I missing anything?

By Ron on Wednesday, June 13, 2001 - 03:23 pm: Edit

Here is a long shot:

Have you had your tranny filter changed recently (60k service)?
I have seen some people seperate the drive shaft at the spline and reattach it. Obviously if you don't put it back on right it will be out of balance.

Ron

By Tate on Wednesday, June 13, 2001 - 03:48 pm: Edit

No recent work on tranny. 30k service was done when I bought it at 40k, so those services are 10k offset. Good try, though. Another bit of "trivia" on the symptoms: they began at the end of a 4 hour drive from DC to Raleigh, NC, all highway miles. A few miles outside of Raleigh, I came off the interstate and noticed the vibes. At that time, they happened at consistent speed bands of 35 and 65 mph. In the course of attempting to get it fixed, the speed bands changed slightly and it became apparant that it's now happening only under driveline load.

By Ron on Wednesday, June 13, 2001 - 03:50 pm: Edit

Have you checked the obvious:

Is there oil in the difs and T-box, are the bolts on the driveshafts tight?

Ron

By Tate on Wednesday, June 13, 2001 - 04:18 pm: Edit

Supposedly the "Rover shop" checked these. I think they're leaking, so that means there's fluid in there, right? Rover dipstick is the trickle down the side ;-) I checked all the driveshaft bolts in the very beginning, and all seemed to be as tight as they could be. I gave everything a good pulling/shaking and didn't observe any appreciable movement. The rear shaft was removed and reinstalled when the rear u-joints were replaced. The tech said the rear joints were "a bit stiff."

By Tate on Monday, June 18, 2001 - 11:30 am: Edit

Just an update: I'm replacing the front u-joints tomorrow. Hopefully that will help. On the 98, the front and rear shafts both take #344. I'm getting two from NAPA for about $27 apiece.

By Milan on Tuesday, June 19, 2001 - 10:00 am: Edit

If your diffs are leaking, it happens under load and if it's not driveshaft or tire related, I'd guess the rear pinion bearing.

Good luck and let us know what it was. Hopefully it's the ujs.

By Tate on Tuesday, June 19, 2001 - 10:30 am: Edit

After replacing the u-joints on the front shaft, the vibes seem to be gone. 3 shops, a month, and $450 later, the problem seems to be fixed. The real test will be on the highway tonight, but in the short test drive, I couldn't get the vibrations back under load going uphill. Thanks for all your collective help in attempting to diagnose this.

By Milan on Tuesday, June 19, 2001 - 02:18 pm: Edit

Good. I actually re-read my message and noticed I misinformed you. It was supposed to read "...if it happens under no load (i.e. when coasting) ... I'd guess the rear pinion bearing." But you said it was under load, so I guess I should read both the enquiries and my replies mor thoroughly.

Sorry. Glad it was just the ujs.