This is a post designed for me to express my dissatisfaction with the ZF automatic... Not in terms of it's service life or strength because it has yet to let me down, but in terms of its operating habits.

I understand that the Land Rover design team's goal was to make this as smoothly operating and comfortable a vehicle as possible, which is an admirable goal for a luxury vehicle. However, now that the truck's intended usgae has been altered (significantly) I am wondering if there is a way to change the shift points and such?

When starting off from a stop, if the pedal is any less than 3/4 of the way to the floor then the trans will immediately shift to second gear... which makes it excessively slow to accelerate.

When the pedal IS to the floor, it shifts from first to second just as the engine is getting into its powerband-- this is most annoying.

I am thinking that I need to tighten up the kickdown cable a bit, that should help some of the drivability issues with the bigger tires. Outside of that, anyone else have an idea on how to change some of these nuisances?

You can adjust the kickdown cable to change the shift points. Some will disagree but I have firsthand experience.
Also if you have stretched the kickdown cable such as during a engine removal or trans removal. Buy not disconecting it before removal. It will act just as you have described. Try disconnecting the shift cable and test driving it. If your symptoms change or go away you have an adjustment problem. Unfortuneatly you cannot leave the shift cable disconnected indefinitely. It will cause damage to the trans. Search this forum for other adjustment discussion. You may have to cut the cable short and recrimp it to get it right.

Jim Pendleton

When the pedal IS to the floor, it shifts from first to second just as the engine is getting into its powerband-- this is most annoying.

really? mine will run its guts out close to 5k before shifting. are you sure the cable just isn't gunked up or something?

other thing to keep in mind is that the shift points were set with a 28" tire on 3.54 gears .. . . yah, it's going to be a bit different now on swampers and 4.10's (IIRC). Shouldn't be hard to find deeper gear set for those toy diffs - i think 4.10 is too high for that size of tire, being the Q78's. just my opnion.

Actually it is still running 3.54s with Q78s, and I don't mind it. It maintains speed on the highway fine too, I just leave the trans in 3rd instead of D and at 70mph the RPMs are at about 3700.

This summer's project is building a 275hp (goal) 3.9L for it, as well as beefing the auto and adding a 1.66 ratio tcase. Should be downright zippy then.

I will try those suggestions Pendy, and let you know how they work out.

Liek Pendy said, the detent cable (proper term) Will adjust the shift pattern enough to makle your truck seem like a rocket.

If you push the throttle to full via the linkage in the engine bay, you should feel a slight detent at the upper most portion of throttle. This is the detent for the accel shift. Most trucks will not hit this detent due to improper setup, or a streached cable. So, with this in mind, you will notice a screww that limits the throttle opening position. You want the detent cable to hit the last detent about an 1/8" from the throttle linkage full open. This will make it so that if you want the truck to go, you simply apply hte gas to the last detent, and the truck will be forced to go into the lowest gear possible at that speed. Sometimes, you will find that if you floor it at highway speeds, the truck will shift down two gears and run really high RPM's (4500RPM) This is jsut fine, and will ultimatly lead to less carbon on the valves as well.

With the detent properly set, your truck will feel like it gained about 50HP+. This was one of the first mods I ever did on my truck when I converted to auto.

It maintains speed on the highway fine too, I just leave the trans in 3rd instead of D and at 70mph the RPMs are at about 3700.



:eek: Damn, that's some high RPM's to be running that engine for long periods of time. I'll run that high to get over a pass, but that's about it.

Nah,

3700 is nothing.

I have been known to be full on 4k plus towing for hours and no issues. Rover V8s like to be beat on. Keeps them happy.

Ron

SUE ROVR is right. Out of all the trucks I worked on at the dealer, the trucks driven by young sporty drivers had fewer engine problems as well as carbon on the valves, than did the pokey soccer moms and such. I drive my D-90 at between 3000-3500RPM's on the highway all the time. Thats where it likes to be. And for reference, my truck has over 110,000 miles on it with very few engine issues.

larry are you joking?

the Rover V8 comes alive at higher RPM and likes to live there... i would cruise with it at 4500rpm without concern so long as the motor was in good condition overall.

edit- and if you would immediately assume that fuel mileage would drop through the floor, I put 350 miles on the truck driving through the mountains at about 50-60mph most of the time, usually in 2nd gear... never 4th, and averaged 12.5mpg. that is with a somewhat tired 3.5L, stock gearing, and 36s with a heeeavy right foot to make it move.

I popped the hood on my D90 as I am also in second gear before I even break the crosswalk on most intersections. What I see is two adjustments one upper and one lower. I tightened up the throttle cable some and see that the lower cable uses two jam nuts to hold it in place. When I press full throttle I do reach a detent right before going full throttle.
My question is however where do I or how do I set the lower cable? the jam nut on the throttle body side was completely off and the one oposite the bracket seemed too loose. I tightened it up some but am not sure how I adequately adjust it? Like I said, right now if you pull the throttle full you do feel the detent right before full throttle but I find it hard to beleive that I set this up blindly and its correct?
Any advice on how to set the other cable?
Thanks
Dennis

Its not really rocket science. As long as you feel the detent a little before full throttle, you should be just fine. The Tranny detent adjust by the two jam nuts you mentioned. You will also notice that the detent cable has a small lead stop around the cable. You should have as much as 1/4" between the lead stop and the end of the threaded cable housing.

Another trick you might find to give you a bit more response, is to drill another hole just above the one that the detent cable hooks into on the throttle, and relocate the cable to that hole. It will raise the shift point even more. This is also how mine is set. Most people are blown away at how fast my seemingly stock D-90 is off the line. Ben tanner never could keep up with me in his standard D-90 with headders etc.

#
0 <--- Throttle hook up
#
#
0 <---Throttle pivot point
#
# <--- Drill new detent hook up here
0 <---Existing detent hook up
#

The shorter time that the detent cable travels along its length, makes the tranny think you are trying to accel faster than normal. Or something like that. I am not sure how to explain it clearly, but it works.

Its not really rocket science. As long as you feel the detent a little before full throttle, you should be just fine. The Tranny detent adjust by the two jam nuts you mentioned. You will also notice that the detent cable has a small lead stop around the cable. You should have as much as 1/4" between the lead stop and the end of the threaded cable housing.

Another trick you might find to give you a bit more response, is to drill another hole just above the one that the detent cable hooks into on the throttle, and relocate the cable to that hole. It will raise the shift point even more. This is also how mine is set. Most people are blown away at how fast my seemingly stock D-90 is off the line. Ben tanner never could keep up with me in his standard D-90 with headders etc.

Now thats a good trick, I did the normal tranny tweaking oh about 8 years ago or more on my old Disco as it was a pig with all the stuff on it, and the hills I had to climb..... I took those mods into the Defender as well...
But I never thought about relocating the thing.... hmmm, add that to the project list!

Thanks KC :smokin:
TomW

nice tech on the detent!

rpm's: what do you think you have under the hood, a chebby?! PFFFTTTTTTTttt - these things are pretty well balanced, all al engine - do not be afraid to rev. I've had mine to 4800 before w/ no problems :eek: and like red regularly go over 4k

You probably have it right. It was just left loose by someone previous to you. Tighten the jam nuts and drive it.

JP

I've read that the stock rover can be revved to about 6500 rpm w/o problems in stock form. But most rovers w/ efi have the factory limiter come in around 5500, give ot take a couple hundred rpm depending on what efi system.
FYI - the bosch 4.0 & 4.6l will rev the highest as they are using lighter weight pistons and the factory adjusted to rev limmiter to account for it.
So, for those of you that have swapped a new bosch 4.0 or 4.6l shortblock into you rover, feel free to rap it out.

Just my .02
Jeff C.

The rev limiter comes into play at about 5800rpm on the Bosch 4.0 in my mother's Range Rover... don't tell her though :D

Literally 10 minutes ago on my way home I had the 3.5 purring at 5k, then I shifted to second. Damn it sounds good, when your only exhaust is a pair of cats and a Y pipe ;)

Hi
There are a number of options to enable you to 'tune' the ZF, as noted the easy fix is the kick down or control cable. This cable pulls a scroll cam which in turn sets the control pressure in relation to throttle position, more throttle more control pressure, more rotational speed needed at the governor to overcome this pressure. There are a multitude of scroll cam profiles available, the scroll cam profile determines the spacing of the shifts. The whole shift pattern can then be moved up or down by selecting a different governor. As the V8 likes to rev if you would like a faster pull away fit a higher stall converter (beware this will generate more heat). The possibilities and combinations available to tune the ZF are endless but before doing anything have an auto box shop carry out a pressure test the best result could be achieved by returning to a stock setting. The only suggestion I have issue with is the 'forced kick down setting', yes this does work exactly as has been noted but on a heavy!! vehicle the double down shift and the sudden application of vast amounts of power can and does lead to he sprag clutch inverting. Result is will not move off in 'D' but once moving after selecting '1' it will continue to drive.
Good luck In-cog-nito

Hi
There are a number of options to enable you to 'tune' the ZF, as noted the easy fix is the kick down or control cable. This cable pulls a scroll cam which in turn sets the control pressure in relation to throttle position, more throttle more control pressure, more rotational speed needed at the governor to overcome this pressure. There are a multitude of scroll cam profiles available, the scroll cam profile determines the spacing of the shifts. The whole shift pattern can then be moved up or down by selecting a different governor. As the V8 likes to rev if you would like a faster pull away fit a higher stall converter (beware this will generate more heat). The possibilities and combinations available to tune the ZF are endless but before doing anything have an auto box shop carry out a pressure test the best result could be achieved by returning to a stock setting. The only suggestion I have issue with is the 'forced kick down setting', yes this does work exactly as has been noted but on a heavy!! vehicle the double down shift and the sudden application of vast amounts of power can and does lead to he sprag clutch inverting. Result is will not move off in 'D' but once moving after selecting '1' it will continue to drive.
Good luck In-cog-nito

Nice first post newbie. I elect you the ZF exspurt.
The torque convertor advice was given to me by MD engineering. It can really awaken a diesel automatic conversion. Moreso then the correct valve bodie even.
You got any valve body reconfigure suggestions neato?

JP

SUE ROVR is right. Out of all the trucks I worked on at the dealer, the trucks driven by young sporty drivers had fewer engine problems as well as carbon on the valves, than did the pokey soccer moms and such. I drive my D-90 at between 3000-3500RPM's on the highway all the time. Thats where it likes to be. And for reference, my truck has over 110,000 miles on it with very few engine issues.

Yep, I can attest to that. I used to work for a dealer and all the trucks that seemed to last forever were driven hard. Most discos are carboned-up coked up slimy grimy inside because people drive them like american V8s.

It is funny that you guys all say that driving Rovers with heavy gas makes them last longer. I have had just the opposite experience with them. My 3.9 likes to be driven grandma style, with low RPM's on the freeway. I try to keep the RPM's down around 2500 for normal freeway driving and maybe max out the RPM's at like 3500 for passing. I consistantly get 19-20mpg on the way to Moab, and my rig is not light by any means. The only time that I have had the motor above 4000 is when I was at the sand dunes and that made me really uncomfortable. But you have to understand that my motor has 200K original miles with no major repairs. So I drive grandma style everywhere.

I hit the rev limiter in my ancient 3.5 today. I think it was at 5100rpm? No catastrophic failures! :D

(secretly trying to blow up this motor so I can put in a hot 3.9L)

Why the hell waste time with that old rust bucket RR?

;)

Why the hell waste time with that old rust bucket RR?

;)

In general, I think every rover owner has a sadistic side....its a shame Adams has come out at such a young age.


So how do you accidently hit 5300 rpm in an automatic range rover?

Who said accidentally? :D I was holding it in first gear climbing a hill from a stop, stock gearing and 36s mean big RPMs to get it moving!! :D

Sorry....when I quickly scanned the post...my brain told me ancient meant "accidently". :shaking: