Hello all

I have a 2000 discovery with 156k miles now and recently I have noticed that my truck will sometimes delay the 4th gear shift until im going 50+ at 3200 RPM. It only does this with the 4th gear and it doesn't always behave in the same manor. It seams that if i drive it more then 20 minutes or if im driving it a little harder then normal it will have this issue. I have also noticed the shift from 3rd to 4th under acceleration is not always a smooth one.

I should also mention that I replaced the ATF some time last year. however i did not replace the filter.

 

I would drop the pan replace the filter and fluid. drive it and do a repeat on the fluid only. add some lucas transmission conditioner. You may find it shifts fine after the first fluid and filter change but for safety I reccomend the second fluid change. gunk build up will come loose and may prematurely begin to clog the filter again. My 2 cents.

 

On many automatic transmissions, these symptoms indicate low fluid level. Have you checked yours?

 

x2 on level. upon changing you need to fill, then cruise the nhood to work the full range of gears, then refill.
i have had low levels cause slow/delayed shifting, sticking and hard shifting

 

Thanks for the replies. I will be checking the level once more and try adding some fluid. If that does nothing I'll change filter and oil out again.

 

Do you know how to check the fluid level?? It can only be checked with the engine running.
When checking see what color the fluid is crystal red or a little brownish.

 

at first glance I thought my fluid was crystal clear but I pulled about a cup out into a jar and i cant see more then an inch into it. Guess its time to change the oil and filter again

 

If it is that bad plan on doing 2 drain and refills, the second one you should consider adding a bottle of Lucas tranny additive.

 

Another thing that can cause issue with 4th gear is the MAFS reading.

I agree with changing out the fluid/filter, but if you are still having issues, and they are solely related to 4th gear, take a look at the MAFS, make sure there is no debris on the screen, and maybe try to clean it.

 

Dave from what I have seen in the past, if the MAF isn't throwing a 100 to a 105 code, but is throwing codes for both banks being rich or lean along with a 734, there is a great chance the MAF is going south, but he hasn't mentioned and fault codes.