I have an issue that has recently ocured with my auto...in a 3.0 auto. When changing up from 3rd to 4th, it does it with a jerk. If I am gentle on the accelerator, it will change fairly smoothly, but if accelerating normally, it changes with a thump. Any ideas on the problem, and/or a remedy?

 

Mine did that fairly soon after I bought it in New Jersey and drove it home to Utah. I decided to change the "filled for life, LOL!", (It had 134,000+ miles on it at that time) transmission fluid. After that change mine was smooth as glass and remains so. I had a hard shift from 3 to 4, 4 to 5, and 5 to overdrive. Down shifting at braking was 3 to 2, and 2 to 1. All of that was corrected.

Here is my thread on the change. Reasons, type of fluid, why I did it this particular way, amounts drained and refilled, etc. Included is explanation of the DEFINITIVE correct level check plug to insure you not remove the wrong one and mess up your transmission shifting.

https://www.jaguarforums.com/forum/x...w-pics-183620/

 

Thanks for your reply Dell.
I purchased my car in December 2019, just before Covid hit. Since we had the biggest Covid lockdown here...I'm in Victoria, Australia it gave my something to do fixing a few little things with the car. It's only done about 160,000 klms...100,000 odd miles and is a nice thing. I really only use it as a Sunday drive. Getting back to the trans issue, you have confirmed what my plan of attack was going to be. Thanks for your information...I'll let you know how it turns out.
Cheers
Adrian