By max200tdi on Monday, October 15, 2001 - 09:47 pm: Edit

G'day all,

I'm seriously contemplating Optimas - the yellow top seems perfect for an aux battery if it can cope with winching & the camping discharging of fridges and flouro lights.

My isolator is the IBS - Swiss made 100 amp smart solenoid type marketed by TJM http://www.tjmproducts.com.au/battery.html
and I've been very happy with it.

Question: which is the lesser of two evils, which will shorten battery life the least - starting regularly on a y/t y/t setup, or charging a r/t y/t setup, breaking the "same make model age" rule?

Despite what the URL says, the instructions say only similar batteries in parallel. As did the guys fitting it.

Starting demands on a Tdi are presumably greater than a V8.

And BTW, I've tried Odesseys, trice the price but didn't last any longer.

Any thoughts?

Regards from downunder
Max P

By jay caragay (Jcaragay) on Monday, October 15, 2001 - 10:32 pm: Edit

I was in the same dilemma back in April. The Yellow Top has a deeper cycle - which (from what I was told) means that you can run anything and everything and run the battery all the way till it dies and it will still take a charge and come back for more.

The Red Top does not have the same depth of charge (hehehe) but has more Cold Cranking Power than the Yellow.

So, perhaps it is more a question of what you will be doing with your Disco. Lots of auxiliary powered stuff like lights, inverters, radios, scanners, refrigerators and blenders (yes!) and you want to run them all without running the engine - then perhaps the Yellow Top is best for you.

I went with the Red Top because of the Cold Cranking Power. I figured that I could use that more because I don't have a blender...

But if I am wrong or off base, the more knowledgeable will come along and kick me to the curb. ;-)

By Moe (Moe) on Tuesday, October 16, 2001 - 04:54 pm: Edit

Max, years ago in the Kimberly I saw farm and mining 4wds running mixed brand dual batteries without problems, and these were driven often and far--fridges being the big draw overnight. But the mixing of batteries is usully to keep costs down and making use of what is available.

A yellow and a red might be a good idea if you think you need the extra starting power, otherwise I would only do that if overnight frosts are common where you live. I have a single yellow top and will put the same on the other side, when I can afford it.

Search the archives here for some good info on this subject.

By warren on Tuesday, October 16, 2001 - 07:02 pm: Edit

Get the Blue Optima Marine Top. I Has more connection points for all of the acessories we put on trucks - Winches, Lights, Air Compressors, And Stereo Systems. It costs a little more but it is worth it.

By Shane C. (Qsiguy) on Wednesday, October 17, 2001 - 02:46 pm: Edit

I wouldn't worry about mixing batteries, provided they are both in good health. If you have an isolator your batteries are only connected while charging, not discharging so they should never draw from each other. I think what you'd be worried about by mixing batteries is if one was trying to charge the other, if you didn't have an isolator. I'd pick a battery for each job that will do that particular job best. That said, I'd personally go with a couple yellow tops because even if you needed the extra cranking amps you can have a switch to use dual battery for cranking. I like deep cycle batteries, I think they last longer especially when you tend work them hard.