Just completed my swap of a 95 Corvette LT1 w/ 4L60E into my 94 Jag XJ6 and am in the process of working out the bugs. Biggest problem to date is that I don't think that I am going into overdrive on the transmission. Going 70 MPH my tach reads about 3000 RPM. Thinking that I should be closer to 2300-2600 RPM also counting the shifts I don't any indication that the trans is shifting into 4th.

Is there some kind of OD selector switch that should be wired up to tell the trans to go into OD? Or do I have a trans issuse? Will the ECM throw some codes if the trans is bad?

Last time I tried to read the ECM I couldn't get the scanner tool to communicate with the ECM. Am still working on that problem.

Any suggestions would be helpful

Thanks Wayne

 

Are you sure it not your t. converter not locking up? Also, what gears do you have in the rear?

 

If your trans is going bad, your fluid will tell you. Either your converter isn't locking up or your trans is going bad. What kind of gears? If you say 2300-2600rpm at 70, sounds like 3.23s or 3.42s.

 

I would probably guess your trans in going bad. I have 3.42's and at 70 my car reads right around 2200-2300rpm's. If I shift my car into 3rd around 70 then it's at about 3000rpm's. I just did this last week because I'm thinking of getting an A3 so I was wondering what it would run like in 3rd.

 

Exactly, no OD indicates that the trans can no longer hold pressure to get OD. This happened to my car, wish i had only realized it earlier.. The car would randomly unlock on the highway. Then recently it unlocked and never locked again. Going about 50mph, i mashed the gas only to have the trans slip and my trans temp's to go crazy!