transmission doesnt want to go into high gear
#21
Front drive shaft came off and cracked the housing of the transmission, that's pretty much quote from shop def gonna have the owner drive it today
#26
#27
I believe the ZF trans is purely mechanical, and shift points are determined based on RPM and fluid pressure. 3K at normal highway cruising speed seems really high, I'm at a little under 2500rpm at 70mph with 245/75/16. When my trans is working right it shifts between 2K - 2500 smooth as silk, when it F's up it shifts at 3K with a bump. I think I read something somewhere once that the ZF has some kind of a failsafe that forces a shift point over 3K but could be thinking of something else or dreaming
Last edited by ajnolin; 06-05-2014 at 09:58 AM.
#28
Got on the highway today and it shifted into high gear (4th) at around 60mph That almost seemed normalish. It's still taking to 3k to get into 3rd which seems a bit of a strain.....I can get up to 2k+ and let off the gas and it will clunk into 3rd. Well at least now I know I must have the right tranny! Headed back to eh shop later today to talk about the hard clunk shifts and the 3rd gear delimea. I'm starting to think Tom is right. Tires have put too much strain on engine/tranny.
Other guys w oversize tires? Are you having similar problems. Also gas consumption is 1/4 tank a day. I'll test the actual mileage when I fill up again.
Other guys w oversize tires? Are you having similar problems. Also gas consumption is 1/4 tank a day. I'll test the actual mileage when I fill up again.
#29
Long Post sorry but interesting
I took my rover back to the garage where I had the used tranny installed. His first comment was I drove it before we put the big tires on and it shifted fine. I saw this coming. I asked him about the governer valve described below, he didnt seem to know what I was talking about. He offered to do a flush and see if that helps. It may. If I understand this valve problem it is inherent when a older transmission has new fluid put in it. The new fluid flushes the tiny debris into place such as this valve that controls shifting.
I found this on rangerovers.net Here is the link
Transmission Diagnosis & Repair
This is part of the article.
Symptoms & Repair of Upshift Problems due to Centrifugal Controller/Governor Malfunction
Winfried Schoepf suddenly experienced shift-up problems on his 1989 Vogue Auto 3.9 EFI. He would have to rev up the engine to 4000 until the ZF 4 HP22 decided to shift. This problem gets worse with time, and the cause is the governor at the rear of the auto box. This is a kind of centrifugal controller for gear shift operations.
I found this on rangerovers.net Here is the link
Transmission Diagnosis & Repair
This is part of the article.
Symptoms & Repair of Upshift Problems due to Centrifugal Controller/Governor Malfunction
Winfried Schoepf suddenly experienced shift-up problems on his 1989 Vogue Auto 3.9 EFI. He would have to rev up the engine to 4000 until the ZF 4 HP22 decided to shift. This problem gets worse with time, and the cause is the governor at the rear of the auto box. This is a kind of centrifugal controller for gear shift operations.