speciman: '98 disco, 143k.
Hello All,

First Issue:
On a cold morning, about 30 degrees, my discoseems to be lacking power.The rpm will rev up to 3500+ just to get the beast moving 20mph. Once it shifts, and i'm going about 35mph the rpm will bounce from 2500 to 3000 until I lay off the gas and let it shift again (very jerky ride). Once it's warmed up, the wierd shifting is gone but it still seems like it's lacking power.

Second Issue:
Little background maintanince history: About a month ago, I had some vibrations in the car driving on the freeway. I took it to the local mechanic and they replaced the back 2 u-joints. Fixed the vibration problem. I started to hear some metal rubbing sound while driving so i replaced the front2 u-joints. Now,here's the issue that I seem to have onlywhenI put the diff lock on.
If i'm going about 60mpg and I lay off the gas and just coast, there is a loud metal rubbing sound. Once it starts, I can hear it while giving it gas, but mostly when i coast. The sound seems to slow down the slower i go and speed up the faster i go. If i take off the diff lock, i can still hear it.

Any direction would be a great help.

thanks
TedIII

 

Have you checked the fluid level in your transfer case? Why are you driving 60 mph with the diff lock engaged? It is my opinion that if the roads are slick enough that you need the diff lock then it's too slick to be driving 60.

 

The first issue, check your transmission fluid level.

The second, have your brakes inspected.

 

Ak- Has a chat with disco Mike and he also suggested checking the transfer case as well as the differentials. My plan for the weekend is flush them.

Spike - Along with the transfer case and differentials, i was planning on flushing the Transmission fluid. Disco Mike suggested that the sensor that determines when the gears to shift could be sticking and a flush would help. As far as the brakes go, I did the front pads about 4 monthes ago and i'll inspect them this week end.

Thanks. I'll let you know.

 

You misunderstood what I said.
First I said that the governor in your tranny wqas sticking and that a fluid change, not a flush, might help. Your tranny is too old to do a flush without possibily killing it.

 

Sorry for the misunderstanding. Didn't know flush and fluid change was different. What is the difference?

 

A fluid flush is hooking a machine to your transmission cooler lines and running all the old fluid out and replacing with new fluid.
A fluid change is a drain and fill, pull the drain plug, refill with new fluid.
Doing the latter will change out about 60% of the old fluid.
This is the prefered metod for older transmissions.
You can repeat the process after a few thousand miles and 90% of your old fluid will be gone.

 

Very busy weekend and with the dump of snow over here I was only able to check the transmission fluid. The fluid was very low and dirty. Emptied a half bottle of Lucas transmission fix and topped the rest off with regular transmission fluid. Immediately, I noticed a difference in the transmission. That has seemed to fix it. I'll have to keep an eye on it to see if there are any leaks. Hopefully, the snow will hold off just enough for me to check out the differentials and transfer case this next weekend.

I'll keep you guys posted. Thanks again.